I have both the lenses - 50/700 and 90/700. Have built Refractors using both. But like the 50/700 is virtually free of chromatic abberation since it's a very slow scope (f/14), the 90/700 has a lot of it since it's a fast scope (f/7.7). This is quite common with large achromatic doublets that have short focal lengths. The image quality is great on both the lenses and can be further improved using Plössl eyepieces. But, if you're very sensitive to chromatic abberation then I don't recommend the 90mm.
@@astroabhi_09 All the best for your build. For both of my scopes I use a dovetail base, which allows me to mount them on any standard camera tripod. If you want to know more about this, then WhatsApp me on 8811856426. But, if you're looking for a standard telescope mount, then the EQ mount by Tejraj is a good option I guess. It costs around ₹5-6k.
You can make some improvements for you 90 mm, like darken the inside of tube, but the best improvement would be to see if you can apply an Anti-reflective coating on the lens. Not sure how much this is possible though. Also you can use two 90 mm /FL=700 in a simple Petzval configuration and get an approx a FL of 1/2 of 700 i.e 350 mm. This becomes a fast F/4. Also you will need to add some field stop between the two lens. You can try the same with a 90 mm and lens of smaller diameter like 70 mm or 60 mm too.
Yes I m also excited to complete my this telescope and No my friend it's not available on Amazon ,but u can get it my mail id is abhishekc921@gmail.com and u can send ur details if u want it, it's cost is 4000.
@@astroabhi_09 I think I might need that lens but the problem is I live in Nepal is their any way of me having that lens? I am very much space enthusiast person can you please help me
Hello thanks for your reply Actually I don't need that for making diy telescope... I made one diy projector and i couldn't find specified triplet lens to focus image as it's not available in india but i came to know that achromatic doublet lens can also product sharp image ,so i was searching achromatic doublet lens of 70-80mm dia and 200-250 focal length ... For now i am using normal convex lens of 200mm fl but image is not sharp... Hope you got me some suggestions to get that specified lens
Buddy u will be amazed after using achromatic doublet lens and focal length should be 500mm so u will get very clear view of planets and deep sky view to....
@@abdulfaheem38 got ur point buddy actually I have one person who made these lens so will Ask him about ur projector lens so wait some time...ok bro...
Bro yes u can see moon but u can't get good details it's will not satisfy you.......so better go for achromatic doublet lence with 700mm fl for best results
Bro abhi mujhe apne tino telescope ko pura use krna h uss k bad hi me catadioptric k bare me soch sakta hu q ki abhi in tino se hi mujhe bohot acha result mil sakta h.......
Bro u need two screws to be tightened with ur Telescope tube on some u can say wooden block or plastic rectangular block 5 cm long that will easily tighten on tripod screw this u can do for fixing....
Sir maine abhi 50mm Achromat Doublet Lens 700mm Focal Length and 25 mm Eyepiece se telescope banayi hai par usase itani acchi image dilhati nahi khali moon ko hi thoda clear dekh sakate hai. Isliye maine abhi 150mm diameter double convex lens with 300mm focal length ki lens mangavaiyi hai to isase telescope ban sakati hai kya or isase gupitor ko clear dekh sakhenge kya?
@@Connecting-nature kafi chije h Jo matter krti h jese Light pollution Pollution Or clear sky Ye sab jab saf hoga tabhi ap ek clear image dekh saknge.....
Hello good morning friend how are you Actually I need a help. Does your friend sell convex lens of 75mm diameter and 250mm focal length? Since many days i am trying to get that but i am not getting ,few i got on Amazon but when i practically check the focal length then it's wasn't 250mm it's was like 400mm and 600mm.. can you please help me in this?
Ok thanks ..I'll be waiting for your reply.. on Amazon i purchased two time from different sellers..but all said it's 75mm dia and 250mm focal length but what product i received was not 250mm focal length.. from one seller i got 400mm focal length lens and from another seller i got 600mm focal length lens . Please ask your friend that if he have ,then check practically regarding focal length... thanks
And focal length is 100% 25cm or 250mm? I just want to confirm this because I have already lost 500rs because they said me they have 75mm dia and 25cm focal length lens but what product which i recieved was not same ..
Brother! Telescope mein ulta bata raha hai, ayesa kyu hota hai? Kiya koi jugard hai iska? Telescope mein upside down na dikhne ke liye kiya karein? Please Brother Batao Na?
@@astroabhi_09 yes you are right I can't find 90mm one, so is 50mm with 25 mm eyepiece is OK for Watching moon and some other objects. Does it have enough magnification and clarity in the image.
Bro for good magnification u use 10mm or 8 mm eyepiece first find out object with 25mm than use smaller mm eye piece because it focus very small area and u should have both eye piece and 50mm is best lenc ,the quality is very good u won't regret after having this...
Hello sir how are you... I just have one doubt..i have one plano convex lens of diameter 75mm and focal length 1000mm and a achromatic doublet lens of diameter 38mm and focal length 200mm.. with this two lens can I make a telescope? If yes then can you explain me and with this what i can see and how much X will me zoom? Thanks
I don't have specified eyepiece ... I just have two lens one is plano convex lens of diameter 75mm and focal length 1000mm and another i have achromatic doublet lens of diameter 38mm and focal length 200mm.. if i consider this 38mm achromatic lens as a eyepiece then can I make a telescope? If yes then how much will be zoom? And what things i can clearly see in space???
@@abdulfaheem38 yes bro and single Plano objective lens not give u clear image u need achromatic lenc and magnification formula = objective lens focal length / eyepiece focal length
Bro ap k yaha tube to hogi to jab wo on ho to Jo apka lens h uski convex side tude k face ki taraf hona chahiye or fr ap k uss lence ko border se pakd ke conx side tube ki tarf kr k fr diwar ki tarf jana dheere 2 and jab wohi tube ki shape puri ajye to waha ruk jao or smjho uski focal length wahi h jo ap k hath me jo lenc h uss k or diwar pr jo image bani h k bich ka distance h focal length...
Apko thoda sasta chahiye to thoda wait krlo me ek 83mm lenc ki vedio dalne wala hu so apko wo thoda sata padega baki agr apko 90mm chahiye to me bat kr k apko batata hu ki sasta mil sakta h ya nai...ok sir
Bro i need to utilise the use of 90mm first and tell everyone about this telescope so after that I can think about that but not now sorry for that but u can go with 50mm it gives u best results I bet on that and it can be under your scale....so all the best bro.....
@@astroabhi_09 yes you are absolutely right bro but I already make optical tube for 90mm and I make duel speed focuser for that that mins in that scope only 90mm lence can fit properly in that
@@astroabhi_09 ji bhaii Iska koi fark nhi pada view pr Bhaii ji agar aap Delhi me Rehte ho to Collab wagairah krte Hain thoda Kisi video me Aapke samne To Mai kuchh bhi nhi Hun Lekin agar aap okay ho to krte Hain fir Collab ♥️♥️♥️
I have both the lenses - 50/700 and 90/700. Have built Refractors using both. But like the 50/700 is virtually free of chromatic abberation since it's a very slow scope (f/14), the 90/700 has a lot of it since it's a fast scope (f/7.7). This is quite common with large achromatic doublets that have short focal lengths. The image quality is great on both the lenses and can be further improved using Plössl eyepieces. But, if you're very sensitive to chromatic abberation then I don't recommend the 90mm.
My 90 is under construction so hope for best what I get from that and I just looking good mounting stand can u help me in that....
@@astroabhi_09 All the best for your build. For both of my scopes I use a dovetail base, which allows me to mount them on any standard camera tripod. If you want to know more about this, then WhatsApp me on 8811856426.
But, if you're looking for a standard telescope mount, then the EQ mount by Tejraj is a good option I guess. It costs around ₹5-6k.
You can make some improvements for you 90 mm, like darken the inside of tube, but the best improvement would be to see if you can apply an Anti-reflective coating on the lens. Not sure how much this is possible though. Also you can use two 90 mm /FL=700 in a simple Petzval configuration and get an approx a FL of 1/2 of 700 i.e 350 mm. This becomes a fast F/4. Also you will need to add some field stop between the two lens. You can try the same with a 90 mm and lens of smaller diameter like 70 mm or 60 mm too.
Kya addres bata sakti hni
@@sanghpriyagautam7290 ki jagh ka address....
Please let me know how this lens performs. I have currently 60 mm lens and kit from Tejraj.
Ok sir....
@@astroabhi_09 What is the problem sir ji ?
There is a 70 mm /500 mm FL from Anand traders. Any idea about this lens ?
@@ranjitneelakandan9551 no i have not used that lenc ..
@@ranjitneelakandan9551 the images i have getting is some kind of blurry images of planets...
Really curious, what image this produces, also how do we get it, is it available on Amazon ?
Yes I m also excited to complete my this telescope and No my friend it's not available on Amazon ,but u can get it my mail id is abhishekc921@gmail.com and u can send ur details if u want it, it's cost is 4000.
@@astroabhi_09 will email you buddy, have some questions about the telescope you made too. Thank you for replying.
Sure bro anytime....
@@astroabhi_09 where I got this lense
Bro i will update you shortly ok about this...
Maa Shaa Allah! 😍😍
Bhai Kahan se kharide ye 90mm lens
What is the general name of this lens
Achromatic doublet lenc.
@@astroabhi_09 I think I might need that lens but the problem is I live in Nepal is their any way of me having that lens? I am very much space enthusiast person can you please help me
@@ishantchamlagain4014 definitely bro u can get this on Amazon i share u like that lens is out of stock when come i let u 9....ok
@@astroabhi_09 thank you bro
This means a lot to me
Hello do you know from where I can find 70-80mm dia and 200-220mm fl achromatic doublet lens in india? If you know please suggest me..
Thanks
Hi bro thanks for watching my video and i need to first find out then i will tell u ok.....so u r looking for deep sky astronomy...
Hello thanks for your reply
Actually I don't need that for making diy telescope...
I made one diy projector and i couldn't find specified triplet lens to focus image as it's not available in india but i came to know that achromatic doublet lens can also product sharp image ,so i was searching achromatic doublet lens of 70-80mm dia and 200-250 focal length ... For now i am using normal convex lens of 200mm fl but image is not sharp...
Hope you got me some suggestions to get that specified lens
Buddy u will be amazed after using achromatic doublet lens and focal length should be 500mm so u will get very clear view of planets and deep sky view to....
Hmm you didn't understand what I was asking anyway it was nice talking to you.. good luck
@@abdulfaheem38 got ur point buddy actually I have one person who made these lens so will Ask him about ur projector lens so wait some time...ok bro...
Osum.....
Can u tell me where to get 90 mm achromatic lens
Yes u can get it from Anand traders but he is busy in some project so u can wait for March they will post 90mm lenc on Amazon
Thank you very much
Isse book ka font bada karke padh sakte han kya
Ha but u can find the magnificent glass in market
Magnifying glass
Ohh yes 😂
90mm ka lens ka link do...
Ok bro wait
Can i see moon with100cm and 50mm focal length lance ,,,,price 245 at flipkart
Bro yes u can see moon but u can't get good details it's will not satisfy you.......so better go for achromatic doublet lence with 700mm fl for best results
Kis len se saturn 🪐 ki ring dikh sakte hai eyepiece kon sa hona chahie
Thanks for comment buddy wese to inn do lens se Aram se dikha jayega apko or clear view chahiye to fir 90mm best h...
Sir mujhe catadioptric teliscopy chahiye
Bro abhi mujhe apne tino telescope ko pura use krna h uss k bad hi me catadioptric k bare me soch sakta hu q ki abhi in tino se hi mujhe bohot acha result mil sakta h.......
Bro how to tightly fix our telescope in our mobile tripod
I will tell u later about this ok bro
@@astroabhi_09 But bro as fast as u can pls tell me
@@astroabhi_09 ok
Bro u need two screws to be tightened with ur Telescope tube on some u can say wooden block or plastic rectangular block 5 cm long that will easily tighten on tripod screw this u can do for fixing....
You should also put
Purchase link
Which place buy this 90mm lense please reply
From anad traders...
Sir maine abhi 50mm Achromat Doublet Lens 700mm Focal Length and 25 mm Eyepiece se telescope banayi hai par usase itani acchi image dilhati nahi khali moon ko hi thoda clear dekh sakate hai. Isliye maine abhi 150mm diameter double convex lens with 300mm focal length ki lens mangavaiyi hai to isase telescope ban sakati hai kya or isase gupitor ko clear dekh sakhenge kya?
Ap kaha rahte h or telescope se kya dekhna chahate h
@@astroabhi_09 Maharashtra.Jupiter, Mars, Saturn moon
Main city Mai....
@@astroabhi_09 nahi
@@Connecting-nature kafi chije h Jo matter krti h jese
Light pollution
Pollution
Or clear sky
Ye sab jab saf hoga tabhi ap ek clear image dekh saknge.....
Eski prize kya hai uttal lence chahiye
90 mm 2lence chahiye
Bro ye apko Amazon pr mil jyega or 4k se upar hi hoga price to
What is cost
Hello good morning friend how are you
Actually I need a help. Does your friend sell convex lens of 75mm diameter and 250mm focal length? Since many days i am trying to get that but i am not getting ,few i got on Amazon but when i practically check the focal length then it's wasn't 250mm it's was like 400mm and 600mm.. can you please help me in this?
Ok bro i ask my friend for that...
Ok thanks ..I'll be waiting for your reply.. on Amazon i purchased two time from different sellers..but all said it's 75mm dia and 250mm focal length but what product i received was not 250mm focal length.. from one seller i got 400mm focal length lens and from another seller i got 600mm focal length lens . Please ask your friend that if he have ,then check practically regarding focal length... thanks
Hello good morning..did you ask your friend?
@@abdulfaheem38 yes bro it's 200rs for len and shipping charges is extra.
And focal length is 100% 25cm or 250mm? I just want to confirm this because I have already lost 500rs because they said me they have 75mm dia and 25cm focal length lens but what product which i recieved was not same ..
I want to purchase 90mm lense, please help me.
Ok sir I will MSG u soon for that
Brother! Telescope mein ulta bata raha hai, ayesa kyu hota hai? Kiya koi jugard hai iska? Telescope mein upside down na dikhne ke liye kiya karein?
Please Brother Batao Na?
Daignol Lelo fr sidha dikhega
Can I know price of 50 mm and 90mm lens and how can I buy it?
Sure bro u can find these on Amazon 50mm easy to find and 90mm can be out of stoct ............
@@astroabhi_09 yes you are right I can't find 90mm one, so is 50mm with 25 mm eyepiece is OK for Watching moon and some other objects. Does it have enough magnification and clarity in the image.
Bro for good magnification u use 10mm or 8 mm eyepiece first find out object with 25mm than use smaller mm eye piece because it focus very small area and u should have both eye piece and 50mm is best lenc ,the quality is very good u won't regret after having this...
@@astroabhi_09 OK thanks for your feedback
Hey Bro is there too much difference in coated and noncoated eyepiece?
Nice💙
Thanks
Yes I want this
Is lens ki madad se kitni dur Tak dekh sakte hain
Bro isse lenc se details kafi clear milti h agr dur ka dekhna h to focal length jada honi chahiye or iss ki 700mm h
does anyone make a 90mm x 1800mm focal length or even a 90mm x 1200mm?
We have only 700mm focal length in 90mm so not possible for higher focal length.
You will need to use a 2x Barlow lens along with this scope.
Better to have less or optimum fl for diameter of lens. Longer fl makes telescopes more sensitive to earth's vibrations
Construí un refractor d 141mm 5 pulgadas y 1200 mm d focal
Didn't understand wat u say....
Hello sir how are you...
I just have one doubt..i have one plano convex lens of diameter 75mm and focal length 1000mm and a achromatic doublet lens of diameter 38mm and focal length 200mm.. with this two lens can I make a telescope? If yes then can you explain me and with this what i can see and how much X will me zoom?
Thanks
What eyepiece do u have bro.....
I don't have specified eyepiece ... I just have two lens one is plano convex lens of diameter 75mm and focal length 1000mm and another i have achromatic doublet lens of diameter 38mm and focal length 200mm.. if i consider this 38mm achromatic lens as a eyepiece then can I make a telescope? If yes then how much will be zoom? And what things i can clearly see in space???
@@abdulfaheem38 5x zoom😂
So it mean i cannot see anything in space... Between how did you calculate zoom with respective to focal length of lens?
@@abdulfaheem38 yes bro and single Plano objective lens not give u clear image u need achromatic lenc and magnification formula = objective lens focal length / eyepiece focal length
Bro this magnifying glass 700mm I want .but I’m from Bangladesh can u send me .and what this price
Thanks for watching my videos and this lens cost to 4k
Or India ke liye kitna cost lagta hai vai
My friend ye india ka hi price h but if I need to send u then it will include courier charges brother....
Thanks vai
90 mm our 900 mm focal kanth vala mirror chahiye
Bro this need to ask is that available or not....
sir focal length kaise calculate karen
Bro ap k yaha tube to hogi to jab wo on ho to Jo apka lens h uski convex side tude k face ki taraf hona chahiye or fr ap k uss lence ko border se pakd ke conx side tube ki tarf kr k fr diwar ki tarf jana dheere 2 and jab wohi tube ki shape puri ajye to waha ruk jao or smjho uski focal length wahi h jo ap k hath me jo lenc h uss k or diwar pr jo image bani h k bich ka distance h focal length...
@@astroabhi_09 ok
How much Rs..it???
It's 4 or 4.5 k ..
Sir 90mmka prise amazone pe 4500 bata raha he kya ye unse bhi sasta he
Apko thoda sasta chahiye to thoda wait krlo me ek 83mm lenc ki vedio dalne wala hu so apko wo thoda sata padega baki agr apko 90mm chahiye to me bat kr k apko batata hu ki sasta mil sakta h ya nai...ok sir
Bro I am waiting for next video
Ok aj ayega1st part of the making of 90mm telescope
Sorry bro for not updating vdo today i will update the vdo in two days as some urgent work is there....
@@astroabhi_09 KB Aayega video bro
Aj ajyega
mujhe 90mm lens lena hai sir, maine aapko mail bhi kiya hai please reply kijiye
Ok i will see and thanks for watching my video ☺️
How much it cost..
4- 4.5k....
@@astroabhi_09 ohh😲
Yes buddy....
❤
Bhai 50 plus ka bata milta h ya nahi...????
Milta h....
@@astroabhi_09 prize kya rahega 80mm ka ...???
Puch kar bataunga bro...
Nice product! What about the price?
Abhi to out of stock but it cost around 4k
कहाँ अर्डर करना होगा? मुझे भि लेना है 90/1000 का
Amazon pr mil jyega ye apko.....
Hello bro how can I contact you
I have some queries to ask
Abhishekc921 insta I'd
And abhishekc921@gmail.com
Bhai kitne ka hai lens
Below 5....
Price kitni hei dono lens ki
Small one will be 1k
Large one will be 4k approx
Vi iska prise kaya ha please bata na
Approx 4000
Price of 90mm lens I need it
Bro i will share u link ok and it cost b/w 4-4.5k
Wow ....
Yes bay
Thanks
I buy this product
Yes u can find it on Amazon..
sir i want too Lions please reply
What?
Ye lens hame Lena hai sir ji
Ok amazon pr milega dekhlo.....
www.astro-optical.com
कहां से खरीदा लेंस
Amazon PR mil jyega but abhi thoda wait krlo q ki abhi issme correction horaha h......
Brother prize kya 90mm dia lens ka
Hi bro thanks for watching my video and price is 4k any if u like it my mail id is abhishekc921@gmail.com u can mail me if you want to buy .
U can better go for 127mm reflector mirror for the same price (but will coast more im construction)...
which is free for any chromatic abbration
👍 good
Nice 👍
Bhai can i get 90mm in 1k or 2k rupees please bhai if you have this extra lence please can you give me bro please 😢😢
Bro i need to utilise the use of 90mm first and tell everyone about this telescope so after that I can think about that but not now sorry for that but u can go with 50mm it gives u best results I bet on that and it can be under your scale....so all the best bro.....
@@astroabhi_09 yes you are absolutely right bro but I already make optical tube for 90mm and I make duel speed focuser for that that mins in that scope only 90mm lence can fit properly in that
Yes i know but it's not that hard to build 50mm and it's very easy and it's result very good l ... So u again can easily build it...
@@astroabhi_09 ok I can try
Bhai you have insta id
Lens ka price kitna sir?
4k sir ji...
Dila do bhai hme bhi
Amazon pr mil jyega bro.....
I want this 90mm achromatic lens
Thanks for watching my video sir and if u want it please message me on abhishekc921 this is my insta id .
Sir, I am not using Instagram, pl give me your WhatsApp number.
😂😂😂 50 MM wale lens me Jo dent Hai wohi same dent mere objective lens me bhi Telescope bnate time girne se aa gya tha 😅😅
Very Nice
Hahaha 😂 yes bro but abhi vdo dala h use usi ka result h koi frk b nai pada h.....
@@astroabhi_09 ji bhaii Iska koi fark nhi pada view pr
Bhaii ji agar aap Delhi me Rehte ho to Collab wagairah krte Hain thoda Kisi video me
Aapke samne To Mai kuchh bhi nhi Hun Lekin agar aap okay ho to krte Hain fir Collab ♥️♥️♥️
@@ambitionworldofficial sure bro bilkul karenge no issues...... And m b kuch b nai hu bro.....
@@astroabhi_09 aap ho 👌🔥
Things Bro Jaldi hi hum koi achha sa topic soch ke and fir milte Hain aapse ♥️
Ok bro ... thanks....
Hii
Hi
I have perses
What?
Hello
Hi
चायना वाला कीमत
Kya bhiya
bhai yah Jo aapane liya hai na aise hi Ek UA-cam per Ne video banaa chuka hai 1100 mein liya hai vah
Please send the link.....