BIAS does not apply to CMOS sensors, only to CCD, and can be detrimental to the CMOS images during calibration, which is what I found was happening with my ASI294MC-P. While researching this and the best way to get rid of amp glow, is when I came across the discussions on how/why CMOS sensors/images cannot be treated like CCD for calibration. Technically, it is physically impossible to shoot a true BIAS frame with a CMOS sensor/camera. The reason is that there is no such thing as a zero exposure time with CMOS cameras (which is required for a true BIAS frame) which typically have a rolling shutter. The appropriate calibration frame set for CMOS sensors is a DARK, FLAT, and DarkFlat. There are some detailed white papers on this and the differences in how to handle CMOS vs CCD imagers. DARKFLATs are identical in all parameters (gain, offset, temp, exposure time), except they are taken with everything covered, same as DARKS. N.I.N.A.'s FlatWizard will automatically create a matched set of FLATS and DARKFLATS. FYI, the USB cable that ZWO provides is something you would give to someone you don't like. Toss it and get a good quality USB cable.
Nice review, Roro! From my perspective, it was perfect: the tune, the specs, the examples (very important!) and the overall calming tone. I am looking at other astro channels and I don't see the same vibe you're bringing. Personally, I enjoy watching you more than the others and this video actually made me decide what to buy for my telescope now. * Great great tune, man! *
Can I ask you what offset you use to capture with? Using the default 30 offset leaves me with strange color variations on the finished image, especially in the red channel. I recently found a forum post on ZWO's site where someone said to shoot with offset 4. I've got that running now and so far it's looking good, just wondering if you encountered similar problems.
@@AstroWithRoRo Ah, the latest ZWO drivers have the offset set to 30 across the board for all cameras. I saw someone with a similar problem on the ZWO forums saying that SharpCap's sensor analysis recommended he use offset=4 and that solved his problem, so last night I tried the same thing but it didn't solve the problem. I'm beginning to wonder if some of these cameras are defective. Unfortunately it's been 37 days since I purchased it so I'm just outside of Agena's return policy. I'm not sure they'll let me return it. :-(
Very helpful video! I could not figure out how to add the 2" lens but can you advise how to now connect the camera to a HyperStar? Or even to the scope? I don't see threads on the lens. Thanks!!
I don't have any experience with HyperStar or SCT telescopes unfortunately so can only guess at what may be the issue. You may need an adapter though for this set up. Generally the camera will either screw into the eyepiece, or be attached by thumb screws with a clamp style attachment.
Very nice production. Technical issues were presented well. You omitted two design feature that should be considered by the customer shopping for astro cameras. First is pixel size. Pixel size is important to get the smallest star shape. The second feature is the sensor shape. This camera has a 4/3 pixel ratio, resulting in a QE ratio of about 75%. This ratio more closely resembles the computer display and printed images, but does not capture most of the light from your optics. Compared to the ZWO ASI533 which has a square sensor resulting in a QE ratio of 85%. The rectangular sensor needs more target planning (camera rotation).
Thanks Michael, I appreciate the feedback. I agree that pixel pitch and the combination of that and resolution matching your focal length and aperture is an important aspect to take into account. The rotational issue and QE definitely plays a part in how you use the cameras. I personally really enjoy the 4:3 aspect ratio of the 294, it feels more "natural" to me, I think as I have been so used to imaging on DSLR's my whole life. I would love to see more square or even circular sensors in the future so we can continue to make better use of the photons our scopes can capture, and ideally remove the need for sensor rotation completely.
@@AstroWithRoRo, regarding the shape of the camera sensor, you will never see a round one. It makes very poor use of the silicon wafer area, thus would be prohibitively expensive. You might see a hexagonal shaped sensor someday. Honey bees found out millions of years ago that shape is very efficient. It would also make good use of the optical plain.
From the HPS site: 256 MB DDR3 memory buffer enables better data transfer stability with "no amp-glow", an issue generated by the slow speed data transfer during readout when connected with a USB2.0 port.
The 294 requires 12v 3A max. This is what I use for the cooling fan (12v 6A max output): www.talentcell.com/products/12v-battery/12v-battery-8300mah.html
If I were to go with an astronomy camera it would be this. It’s itty bitty and has a good sensor. And I use micro four thirds so that small sensor is something I’m used to. But I’ll stick to mirrorless cameras for now
Tough decision. Make sure you check astronomy.tools for your scope & the cameras to check out your field of view and the CCD comparability guide for sampling rates. That may help you decide!
Thanks Nick, I wasn’t able to find it directly from ZWO in my research so only mentioned it in passing during the video. If you have a link, I’ll add some annotations to clarify and link it in the description.
@@AstroWithRoRo Cloudy nights forums and some other ones as well, Also the ZWO cameras facebook site, I can't remember offhand where but with astronomy CMOS cameras bias frames are discouraged in favour of dark flats
Background music absolutely nerve wracking and completely uncalled for, otherwise this would have been a very informative video. Would not subscribe to watch any more offerings from his channel....
Great job man. Well shot, and well thought out video.
Thanks James, appreciate the feedback!
Another great astro channel ! Subscribed
Thanks for the feedback!
BIAS does not apply to CMOS sensors, only to CCD, and can be detrimental to the CMOS images during calibration, which is what I found was happening with my ASI294MC-P. While researching this and the best way to get rid of amp glow, is when I came across the discussions on how/why CMOS sensors/images cannot be treated like CCD for calibration. Technically, it is physically impossible to shoot a true BIAS frame with a CMOS sensor/camera. The reason is that there is no such thing as a zero exposure time with CMOS cameras (which is required for a true BIAS frame) which typically have a rolling shutter. The appropriate calibration frame set for CMOS sensors is a DARK, FLAT, and DarkFlat. There are some detailed white papers on this and the differences in how to handle CMOS vs CCD imagers. DARKFLATs are identical in all parameters (gain, offset, temp, exposure time), except they are taken with everything covered, same as DARKS. N.I.N.A.'s FlatWizard will automatically create a matched set of FLATS and DARKFLATS.
FYI, the USB cable that ZWO provides is something you would give to someone you don't like. Toss it and get a good quality USB cable.
Nice review, Roro! From my perspective, it was perfect: the tune, the specs, the examples (very important!) and the overall calming tone. I am looking at other astro channels and I don't see the same vibe you're bringing. Personally, I enjoy watching you more than the others and this video actually made me decide what to buy for my telescope now.
* Great great tune, man! *
Thanks so much for the feedback, it's great to hear you liked the video and it helps you on a decision!
Can I ask you what offset you use to capture with? Using the default 30 offset leaves me with strange color variations on the finished image, especially in the red channel. I recently found a forum post on ZWO's site where someone said to shoot with offset 4. I've got that running now and so far it's looking good, just wondering if you encountered similar problems.
I haven’t had to touch my offset at all and have left it at the default setting. I just checked and it’s set to 8 in ASICAP.
@@AstroWithRoRo Ah, the latest ZWO drivers have the offset set to 30 across the board for all cameras. I saw someone with a similar problem on the ZWO forums saying that SharpCap's sensor analysis recommended he use offset=4 and that solved his problem, so last night I tried the same thing but it didn't solve the problem. I'm beginning to wonder if some of these cameras are defective. Unfortunately it's been 37 days since I purchased it so I'm just outside of Agena's return policy. I'm not sure they'll let me return it. :-(
Very helpful video! I could not figure out how to add the 2" lens but can you advise how to now connect the camera to a HyperStar? Or even to the scope? I don't see threads on the lens. Thanks!!
I don't have any experience with HyperStar or SCT telescopes unfortunately so can only guess at what may be the issue. You may need an adapter though for this set up. Generally the camera will either screw into the eyepiece, or be attached by thumb screws with a clamp style attachment.
Very nice production. Technical issues were presented well. You omitted two design feature that should be considered by the customer shopping for astro cameras.
First is pixel size. Pixel size is important to get the smallest star shape.
The second feature is the sensor shape. This camera has a 4/3 pixel ratio, resulting in a QE ratio of about 75%. This ratio more closely resembles the computer display and printed images, but does not capture most of the light from your optics. Compared to the ZWO ASI533 which has a square sensor resulting in a QE ratio of 85%. The rectangular sensor needs more target planning (camera rotation).
Thanks Michael, I appreciate the feedback. I agree that pixel pitch and the combination of that and resolution matching your focal length and aperture is an important aspect to take into account.
The rotational issue and QE definitely plays a part in how you use the cameras. I personally really enjoy the 4:3 aspect ratio of the 294, it feels more "natural" to me, I think as I have been so used to imaging on DSLR's my whole life. I would love to see more square or even circular sensors in the future so we can continue to make better use of the photons our scopes can capture, and ideally remove the need for sensor rotation completely.
@@AstroWithRoRo, regarding the shape of the camera sensor, you will never see a round one. It makes very poor use of the silicon wafer area, thus would be prohibitively expensive. You might see a hexagonal shaped sensor someday. Honey bees found out millions of years ago that shape is very efficient. It would also make good use of the optical plain.
Love that idea! Hexagonal would indeed be sexy.
From the HPS site:
256 MB DDR3 memory buffer enables better data transfer stability with "no amp-glow", an issue generated by the slow speed data transfer during readout when connected with a USB2.0 port.
Excellent! I just got one of these!
Good choice!
Very informative well done
Glad it was helpful!
Could you share the links to the power source to see the specs?
The 294 requires 12v 3A max. This is what I use for the cooling fan (12v 6A max output):
www.talentcell.com/products/12v-battery/12v-battery-8300mah.html
If I were to go with an astronomy camera it would be this. It’s itty bitty and has a good sensor. And I use micro four thirds so that small sensor is something I’m used to. But I’ll stick to mirrorless cameras for now
I've got no connectivity issues with this camera so may not be a model/design issue
Tried to watch but your background music is far too loud to hear you talk.
Thanks for the feedback Paul, will work I’m getting the EQ better in the next one.
@@AstroWithRoRo 👍🏻 interested in this camera. Well it's a toss up between this and the 533. Can't decide 😩
Tough decision. Make sure you check astronomy.tools for your scope & the cameras to check out your field of view and the CCD comparability guide for sampling rates. That may help you decide!
@@AstroWithRoRo yeah have done and the 183 actually comes out better under normal skies but I'm leaning towards these other 2.
@@paulradford6902 cuiv the lazy geek recommends the 533 over the 264 in heavy light polluted skies.
No need for bias frames with these cameras just pointin this out even ZWO says bias frames are unecessary, take darks, flats and dark flats
Thanks Nick, I wasn’t able to find it directly from ZWO in my research so only mentioned it in passing during the video. If you have a link, I’ll add some annotations to clarify and link it in the description.
@@AstroWithRoRo Cloudy nights forums and some other ones as well, Also the ZWO cameras facebook site, I can't remember offhand where but with
astronomy CMOS cameras bias frames are discouraged in favour of dark flats
Interesting review thanks. Spoilt by the 'music' sadly
Background sound too high!!! Have to quit viewing!!
Background music absolutely nerve wracking and completely uncalled for, otherwise this would have been a very informative video. Would not subscribe to watch any more offerings from his channel....
Thanks for the feedback Josedav, I have made sure that my newer videos do not suffer this same issue.
I doesn’t agree, except the music volume is little high, if it were only background is a nice theme
Thanks for the feedback. It’s perhaps too intense of a tune.