SV220 Dual band Narrowband Filter Review
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- Опубліковано 2 сер 2024
- The new SV220 is SVBONs first venture into a dual-narrowband filter. Its surprising good and I had a lot of fun testing it out. In this video I summarized my thoughts about it and show what equipment to use. I found that with the correct arrangement of the filter and focal reducer, this filter can turn out some excellent results. Light pollution is essentially almost completly gone. You will really have to treat this filter like a narrowband filter though. Exposure times have to be very long in order to get good take full advantage of it.
Link to the filter specs in further detail.
www.svbony.com/sv220-dual-ban... - Наука та технологія
that's an excellent idea! I liked the way you put that filter in front of the reducer!!
very nice video and well explained
Great video, thank you. And that is the first explanation of how halos are created. Now I know, it all makes sense.
Glad you enjoyed it!
Just picked one of these up. Vintage lens enthusiast and it worked flawlessly with my 135mm takumar f3.5 lens. Only got 10 minutes of data before my mount died but very happy with the result. No halos with an Altair astro Hypercam 533.
Thanks for the explanation of DBNF's!
Cuiv just reviewed the SV220 and was impressed with its performance for the price, but this video convinced me to order one.
Amazon currently has the 1.25" for $110, & 2" for $160 (US).
so it's good 👍 ...
can't wait for your 269 sensor review
As soon as possible
Quite nice. May get one.
Seems a good filter, plus it's extremely relevant when you consider your channels name!
Also, I don't own a telescope. I'm not sure why I'm here, but I enjoy the videos nonetheless 😁.
I don't even have a tracker 😅 only my camera and cheap 100$ tripod 😬 I still try astrophotography though 💪
Thank you. That is high praise indeed.
Have you tried the sv226 SHO 2" 5nm set by svbony? I don't see any reviews for it anywhere.
Thanks for the explanation of halos. My awareness, interest in this filter comes on the heels of a review on the Altair dual narowband by delta asttro. Numerous commentators mentioned using the SV220. THE Altaire comes with a chart "proving" it's claim of accuracy. Do you think the SV220 is narrow enough to potentially miss the mark, and not pass the "good" light?
Maybe I've been watching too many "lazy geek " videos.
great to hear as I'm due to receive mine in a week or so and my placement fits what your saying , going to using step down rings to mount it to the front of the Samyang and mounting it on the bottom of the CC i have for the 130pds ( skywatcher aplanatic corrector) .
Whoa, this, paired with a farther filter position, tamed Alnitak? Dang son. Now I'm wondering who will win in a shoot-off between this and the STC duo-narrowband filter (given how close it is to the sensor). I need to think through my use cases (eg an OM1 and Roki 135 OTA with either the Star Adventurer 2i or GTi as my ultraportable, plane-compatible, self-sufficient OSC rig) if it's worth it to sell the STC and get this filter instead.
And hey, no pressure on the SV550, weather has been weird these past few months. I hope you get enough clear skies in time for 2022 E3 (ZTF), that bad boi has some funky tail action happening, it's totally worth staying up late for.
Clear skies, clean glass!
If the STC is coated for reflections it will not have any halos. I do not think I remember ever seeing any with that filter.
Great idea about filter placement. I do wonder if this filter would play nice with an F/2 system like the Hyperstar. 7nm should be wide enough even given the spectrum shift of fast optics. Hummm
Its wide enough for sure however you would have to place it closer to the sensor.
I understand the principle of dual band narrowband imaging for collecting emission light from nebulae and the process of extracting O3 and Ha from the images during post. Currently, however, I do not own a monochrome camera, just a colour OSC camera. That’s where I’m a bit lost: I expect it will require much greater exposure to these two emission bands in order to yield an interesting image, but how and how much?
Does that translate into exposure times that are double or triple the normal time (e.g. say 2 or 3 x 300s)? Or does it require 2 to 3 times more images (SNR) of the normal exposure time? Or a combination of both?
In short: what are the rules of thumb for using a dual band narrowband filter on an OSC camera? (Besides the back focus and the halo reduction strategies)
Simply put you have to treat your OSC camera likes its a mono camera and user very long exposures. This is a good thing though the mono camera can do it with greater resolution.
Ok, I'm using zwo 533mc pro (color), in bortle 8. With this filter (guiding aside), how long would one recommend my subs be?
A question if I may... why would exposure times have to be increased when using this dual narrow band filter since the light from emission nebulas is precisely from within those bands ?
Yes you get to take very long exposures with this which gets you way more detail in a single exposure.
Great explanation, something I never knew. Strange thing is with my 72ED doublet and flattener I get halos when using my L-Extreme but when I shoot with my newt and coma corrector I don't, not sure why.
That is interesting. Do you know if there is a difference in the distance of your filter from the sensor? Also is there a difference in the f ratio between them?
@@TheNarrowbandChannel distance is identical both 55mm and both scopes are f5, weird, maybe the CC is better coated?
I know this video is a little dated , but did you see any flat frame issues with the 294mc? I have seen color blotches from other brands of dual band filters?
I do not have a 294mc. I have the mono version which is an all together different sensor.
Do you know if the om-1 night vision has any influence on the photo quality when shooting with it active? Or can it just be turned on all the time you shoot? I don't seem to notice big difference, but I don't have a computer to see the full details. I normally use it to find my goal and then turn it off.
It does not. What it does is slow the frame rate so longer exposures can be taken giving a better view in the dark.
@@TheNarrowbandChannel so 20 seconds shutter actually becomes more like 30 seconds when using it? If I understand correctly 😬
@@bamsemh1 More like 300s exposures. But trust me that is a good thing. It's mean 10X as much signal in a single exposure without getting overexposed.
Would this filter work good with a f4.8 telescope without any shifting?
Yes. Its a wide enough band pas.
Soo very interesting. When people buy a good quality astrophotography camera is one good enough or several? Because there are endless camera and lens videos. 😎 Thank you.
This hobby is a very gear hungry one.
SVBONY, makes or should I say sells good Astro EQ, not the best but not the worse! There scopes are not made by them as most of there other items with SVBONY's name on the item, and same with their filters and for entry or beginners a good way to get good EQ for the lowest cost.
I used to be interrested but... I'm a color peeper. I need colors to be accurate, and you know what :
hydrogen is not red, only its alpha line is. All images with bright red hydrogen makes my eyes scream and my mouth opens wide in shock :D Also... damn blue stars.
Now... maybe I can still use this as a luminance layer...
grrrr, I still need to separate hydrogen from oxygen if I want to calibrate colors correctly.
arg, so many filters needed, stupid bright sky.
I think what you need then is a mono camera. :) Hydrogen just about always overwhelms all other colors in space. Even Hubble which has 0 light pollution still uses narrowband imaging filters.
@@TheNarrowbandChannel oh that would be ideal... after getting an actual telescope instead of a photo lens, and after a good computerized mount to guide and dither, and after the filter wheel cause switching and refocussing manually is yerk, and after selling my car, my house... but I need to buy a car and a house before that :D
Hello, sorry to write this comment' : filter in front of corrector, this is just what you have to do if you want to lost a big part of efficiency (QE of filter) and other optic problem's. It
work, but with a bad efficiency. Sorry for this comment, viewer have to know your information is wrong with filter position you said.... If there is halos, tha't just the filter conception is not good enought. that's why there is 500 dollars filters and 100 dollars filter, quality is not the same.
First never be sorry to write a comment. All feedback is good. It is how we learn.
Second where did you hear that filter distance changes QE? I have never heard of this before and using different filter distances has never affected QE noticeably for me.
Halos come from reflections of the filter. It is not an AR coated filter so it has them but like I said in the video you can minimize them by placing the filter such that it is defused enough to be less noticeable.
@@TheNarrowbandChannel to complete in details : a filter at the input of a corrector causes you to lose a more or less significant EQ, depending on its design and initial restrictivity. A filter is designed to filter the light signal at a specific, well-defined angle (with a margin, of course - the physics of optics and wave propagation through a solid). If you attack a filter with an unsuitable angle (before a corrector, for example), at best your filter will simply have a drop in its EQ, and with bad filters it will have additional aberrations (filter shift, signal fadding, etc.). - If there are halos when the filter is in the right place (close to the sensor), it's because the filter isn't perfectly designed, with halos generated by a small diffraction of the waves linked to its design, but this is to the benefit of a theoretically guaranteed filtered wavelength - yes, depending on the angle of attack, the filtered signal may shift a little too (a fairly negligible aspect most of the time) - antlia or nbz, for example, don't produce these halos, but they cost 2 to 3 times more than the others: / ) unfortunately we have to pay for quality :/ . However, using it as a corrector input will give you a result, and it still works more or less correctly until you put in a filter drawer. That's why brands have developed filters with adapted FD ratios, below FD3 for example for "fast" filters and above FD4 for the classic category, because their design and the deposits of the "filtering" layers are arranged differently in order to maintain the desired EQ and characteristics according to the FD of the instrument and the angle of attack on it.
Oh I am putting the filter behind the corrector not in front of it. Also light in front of the reducer will be less acute since the F number is higher at that point. So really if it was set up that way it would not be an issue.
Also most of what you are talking about only applies to very narrow files in the 5nm and narrow range. Not for filters as wide as 6.5nm You can watch Cuiv the Lazy Geek, he has some good description of how this works.@@ShipmunksPix