Electronic shutter on the Sony A7R II

Started 4 months ago | Discussions
Igor Sotelo Regular Member • Posts: 461
Electronic shutter on the Sony A7R II

I'm slowly started to understand how astrophotography is done, and apparently one takes thousands of pictures for selection and stacking.

Was thinking to use my DSLR's but the mechanical shutter on those cameras is limited to only 100K to 200K actuations. Probably also causing vibration of repeated use.

Till I get a telescope, could use some of my Canon or Nikon telephotos with a planetary/DSO camera, but those lenses are mainly AF with very short throw for precise adjustments.

Another option is the Sony A7R II using AF adapters or native FE lenses. While the shutter is rated for 500K, has the option to use electronic shutter in a silent mode which probably causes less stress to the camera over time.

But will the sensor or the electronics get damaged because of high electronic shutter count? Will rolling shutter be an issue? The A7R II apparently also has some star "eating" algorithms when +30s exposure are used, not sure if that will be a problem? Maybe the sensor will get burned by the sun even when using ND filters?

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Sony a7R II
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Tristimulus Veteran Member • Posts: 7,555
Re: Electronic shutter on the Sony A7R II
1

Igor Sotelo wrote:

I'm slowly started to understand how astrophotography is done, and apparently one takes thousands of pictures for selection and stacking.

Was thinking to use my DSLR's but the mechanical shutter on those cameras is limited to only 100K to 200K actuations. Probably also causing vibration of repeated use.

Why care?

Most cameras are replaced long before the shutter wear down anyway.

Till I get a telescope, could use some of my Canon or Nikon telephotos with a planetary/DSO camera, but those lenses are mainly AF with very short throw for precise adjustments.

If your camera have silent shooting vibration should be no issue.

High quality solar, lunar and planetary images are taken with video cameras. Search for lucky imaging, a technique to get detailed images.

Another option is the Sony A7R II using AF adapters or native FE lenses. While the shutter is rated for 500K, has the option to use electronic shutter in a silent mode which probably causes less stress to the camera over time.

But will the sensor or the electronics get damaged because of high electronic shutter count?

No.

Will rolling shutter be an issue?

Not for astronomy.

The A7R II apparently also has some star "eating" algorithms when +30s exposure are used, not sure if that will be a problem?

No real life problem unless using the very best optics and guiding is impeccable. Worst case is that some of the faintest stars turn greenish (RGGB Bayer filter matrix).

Maybe the sensor will get burned by the sun even when using ND filters?

That applies to all mirrorless cameras.

Taking ordinary images where the sun is part the picture is no problem (the IR filter takes care of short term heat). Letting the sun shine into the camera for a prolonged time will cause problems. Simply use a proper solar filter - not ND filters.

Alen K
Alen K Senior Member • Posts: 1,271
Re: Electronic shutter on the Sony A7R II

For deep-sky astrophotography, mechanical shutter life is not much of a problem because most people mount the camera or telescope/camera combination on some sort of tracking platform, be it a portable tracker or a full-blown equatorial mount. Exposures in that case are typically at least 30 seconds to several minutes long. Only tens to hundreds of sub-exposures are then required for typical total exposure times.

Shutter life could potentially be a problem if attempting to do long total exposures with an untracked camera, since sub-exposures would necessarily be much shorter, perhaps only a couple of seconds. If you try this, you will soon tire of it and buy a tracker.

Planetary and lunar close-up astrophotography, on the other hand, is best done with thousands of short (1/30 second or shorter) exposures in order to get enough candidates that are either wholly or partly minimally effected by atmospheric turbulence. (I am oversimplifying.) Special stacking software is then used to automatically sort through the frames to find the best ones and then aligning and combining them.

Practically speaking, that means taking video, not individual exposures. Furthermore, the video should preferally be uncompressed, something that most of today's DSLRs and mirrorless cameras can't do without extra secondary equipment. It is far more practical (and less expensive) to use a dedicated planetary camera feeding video over USB to a computer.

Note that planetary and lunar close-up astrophotography requires a lot of image scale, at least if you want to capture any actual detail. In practise, that means attaching the camera to a telescope, the larger the better. Telephoto lenses just won't cut it, so any concerns about the design of such lenses (autofocus, etc) in that context is misplaced. You wouldn't be using them for that purpose in any case.

1llusive
1llusive Veteran Member • Posts: 3,425
Re: Electronic shutter on the Sony A7R II

Alen K wrote:

For deep-sky astrophotography, mechanical shutter life is not much of a problem because most people mount the camera or telescope/camera combination on some sort of tracking platform, be it a portable tracker or a full-blown equatorial mount. Exposures in that case are typically at least 30 seconds to several minutes long. Only tens to hundreds of sub-exposures are then required for typical total exposure times.

Shutter life could potentially be a problem if attempting to do long total exposures with an untracked camera, since sub-exposures would necessarily be much shorter, perhaps only a couple of seconds. If you try this, you will soon tire of it and buy a tracker.

Planetary and lunar close-up astrophotography, on the other hand, is best done with thousands of short (1/30 second or shorter) exposures in order to get enough candidates that are either wholly or partly minimally effected by atmospheric turbulence. (I am oversimplifying.) Special stacking software is then used to automatically sort through the frames to find the best ones and then aligning and combining them.

Practically speaking, that means taking video, not individual exposures. Furthermore, the video should preferally be uncompressed, something that most of today's DSLRs and mirrorless cameras can't do without extra secondary equipment. It is far more practical (and less expensive) to use a dedicated planetary camera feeding video over USB to a computer.

I believe taking fast electronic shutter frames is better than video. Part of the reason you alluded to is compression, but the other reason is avoiding over sampling or line skipping of the sensor and just getting a raw 1:1 pixel mapping.

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Alen K
Alen K Senior Member • Posts: 1,271
Re: Electronic shutter on the Sony A7R II
1

1llusive wrote:

Alen K wrote:

For deep-sky astrophotography, mechanical shutter life is not much of a problem because most people mount the camera or telescope/camera combination on some sort of tracking platform, be it a portable tracker or a full-blown equatorial mount. Exposures in that case are typically at least 30 seconds to several minutes long. Only tens to hundreds of sub-exposures are then required for typical total exposure times.

Shutter life could potentially be a problem if attempting to do long total exposures with an untracked camera, since sub-exposures would necessarily be much shorter, perhaps only a couple of seconds. If you try this, you will soon tire of it and buy a tracker.

Planetary and lunar close-up astrophotography, on the other hand, is best done with thousands of short (1/30 second or shorter) exposures in order to get enough candidates that are either wholly or partly minimally effected by atmospheric turbulence. (I am oversimplifying.) Special stacking software is then used to automatically sort through the frames to find the best ones and then aligning and combining them.

Practically speaking, that means taking video, not individual exposures. Furthermore, the video should preferally be uncompressed, something that most of today's DSLRs and mirrorless cameras can't do without extra secondary equipment. It is far more practical (and less expensive) to use a dedicated planetary camera feeding video over USB to a computer.

I believe taking fast electronic shutter frames is better than video. Part of the reason you alluded to is compression, but the other reason is avoiding over sampling or line skipping of the sensor and just getting a raw 1:1 pixel mapping.

Better for quality, yes. But I'm not sure the stacking programs I alluded to (e.g., Autostakkert!) can handle thousands or even mere hundreds of such frames. They are happier with video files, which even if uncompressed are usually smaller than the equivalent number of still pictures because each frame in the video file will have lower resolution. (Even if you were to use 4K video, which is equivalent to around 8 megapixels.)

And how many frames per second can be achieved using the electronic shutter still-image mode? Most planetary and lunar imagers recommend at least 30 fps, with 60 fps being better. The idea is to freeze the seeing as much a possible in each frame and to collect as many frames as possible in a given time in order to have more candidates for selection.

One of the other problems with using video from most DSLRs or mirrorless cameras, besides video compression and line skipping or averaging, is that you don't usually need the field of view their large sensors provide. Certainly when imaging planets, most of the frame will be empty and hence wasted.

That is yet another reason to use a dedicated planetary/lunar camera with their smaller sensors. Such cameras avoid all of the problems we have mentioned. All of the top planetary and lunar imagers use them. I'm not saying that a mirrorless camera can't be used for imaging planets or lunar close-ups. But they are not ideal for that.

1llusive
1llusive Veteran Member • Posts: 3,425
Re: Electronic shutter on the Sony A7R II

Alen K wrote:

1llusive wrote:

Alen K wrote:

For deep-sky astrophotography, mechanical shutter life is not much of a problem because most people mount the camera or telescope/camera combination on some sort of tracking platform, be it a portable tracker or a full-blown equatorial mount. Exposures in that case are typically at least 30 seconds to several minutes long. Only tens to hundreds of sub-exposures are then required for typical total exposure times.

Shutter life could potentially be a problem if attempting to do long total exposures with an untracked camera, since sub-exposures would necessarily be much shorter, perhaps only a couple of seconds. If you try this, you will soon tire of it and buy a tracker.

Planetary and lunar close-up astrophotography, on the other hand, is best done with thousands of short (1/30 second or shorter) exposures in order to get enough candidates that are either wholly or partly minimally effected by atmospheric turbulence. (I am oversimplifying.) Special stacking software is then used to automatically sort through the frames to find the best ones and then aligning and combining them.

Practically speaking, that means taking video, not individual exposures. Furthermore, the video should preferally be uncompressed, something that most of today's DSLRs and mirrorless cameras can't do without extra secondary equipment. It is far more practical (and less expensive) to use a dedicated planetary camera feeding video over USB to a computer.

I believe taking fast electronic shutter frames is better than video. Part of the reason you alluded to is compression, but the other reason is avoiding over sampling or line skipping of the sensor and just getting a raw 1:1 pixel mapping.

Better for quality, yes. But I'm not sure the stacking programs I alluded to (e.g., Autostakkert!) can handle thousands or even mere hundreds of such frames. They are happier with video files, which even if uncompressed are usually smaller than the equivalent number of still pictures because each frame in the video file will have lower resolution. (Even if you were to use 4K video, which is equivalent to around 8 megapixels.)

And how many frames per second can be achieved using the electronic shutter still-image mode? Most planetary and lunar imagers recommend at least 30 fps, with 60 fps being better. The idea is to freeze the seeing as much a possible in each frame and to collect as many frames as possible in a given time in order to have more candidates for selection.

One of the other problems with using video from most DSLRs or mirrorless cameras, besides video compression and line skipping or averaging, is that you don't usually need the field of view their large sensors provide. Certainly when imaging planets, most of the frame will be empty and hence wasted.

That is yet another reason to use a dedicated planetary/lunar camera with their smaller sensors. Such cameras avoid all of the problems we have mentioned. All of the top planetary and lunar imagers use them. I'm not saying that a mirrorless camera can't be used for imaging planets or lunar close-ups. But they are not ideal for that.

We can do 30 fps at 2160p on the current Nikons and a firmware update coming in February will give us 60 fps at 2160p with a 1.5x crop. Sounds like it's worth trying.

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Jeffry7 Regular Member • Posts: 401
Re: Electronic shutter on the Sony A7R II

Alen K wrote:

1llusive wrote:

Alen K wrote:

For deep-sky astrophotography, mechanical shutter life is not much of a problem because most people mount the camera or telescope/camera combination on some sort of tracking platform, be it a portable tracker or a full-blown equatorial mount. Exposures in that case are typically at least 30 seconds to several minutes long. Only tens to hundreds of sub-exposures are then required for typical total exposure times.

Shutter life could potentially be a problem if attempting to do long total exposures with an untracked camera, since sub-exposures would necessarily be much shorter, perhaps only a couple of seconds. If you try this, you will soon tire of it and buy a tracker.

Planetary and lunar close-up astrophotography, on the other hand, is best done with thousands of short (1/30 second or shorter) exposures in order to get enough candidates that are either wholly or partly minimally effected by atmospheric turbulence. (I am oversimplifying.) Special stacking software is then used to automatically sort through the frames to find the best ones and then aligning and combining them.

Practically speaking, that means taking video, not individual exposures. Furthermore, the video should preferally be uncompressed, something that most of today's DSLRs and mirrorless cameras can't do without extra secondary equipment. It is far more practical (and less expensive) to use a dedicated planetary camera feeding video over USB to a computer.

I believe taking fast electronic shutter frames is better than video. Part of the reason you alluded to is compression, but the other reason is avoiding over sampling or line skipping of the sensor and just getting a raw 1:1 pixel mapping.

Better for quality, yes. But I'm not sure the stacking programs I alluded to (e.g., Autostakkert!) can handle thousands or even mere hundreds of such frames. They are happier with video files, which even if uncompressed are usually smaller than the equivalent number of still pictures because each frame in the video file will have lower resolution. (Even if you were to use 4K video, which is equivalent to around 8 megapixels.)

And how many frames per second can be achieved using the electronic shutter still-image mode? Most planetary and lunar imagers recommend at least 30 fps, with 60 fps being better. The idea is to freeze the seeing as much a possible in each frame and to collect as many frames as possible in a given time in order to have more candidates for selection.

One of the other problems with using video from most DSLRs or mirrorless cameras, besides video compression and line skipping or averaging, is that you don't usually need the field of view their large sensors provide. Certainly when imaging planets, most of the frame will be empty and hence wasted.

That is yet another reason to use a dedicated planetary/lunar camera with their smaller sensors. Such cameras avoid all of the problems we have mentioned. All of the top planetary and lunar imagers use them. I'm not saying that a mirrorless camera can't be used for imaging planets or lunar close-ups. But they are not ideal for that.

I have run hundreds of frames of photographic stills through autostakkert. My biggest single stack was just shy of 700 frames.

It didn't have a problem with this.

Alen K
Alen K Senior Member • Posts: 1,271
Re: Electronic shutter on the Sony A7R II

Jeffry7 wrote:

I have run hundreds of frames of photographic stills through autostakkert. My biggest single stack was just shy of 700 frames.

It didn't have a problem with this.

Good to know. How big were the frames?

Jeffry7 Regular Member • Posts: 401
Re: Electronic shutter on the Sony A7R II
1

Alen K wrote:

Jeffry7 wrote:

I have run hundreds of frames of photographic stills through autostakkert. My biggest single stack was just shy of 700 frames.

It didn't have a problem with this.

Good to know. How big were the frames?

After cropping with PIPP, they were 2400X2400. The files where around 13MB.

Greg Campbell Junior Member • Posts: 28
Re: Electronic shutter on the Sony A7R II
1

Silent shutter is a wonderful thing when shooting lots of images. Time-lapse, lightning, short exposure astro, etc. The reduction in vibration and - yes - mechanical wear and tear is worthwhile. (I honestly can't fathom the crowd that argue against the increased longevity. I guess they see cameras as trivial and disposable?!) The only drawback is that some cameras drop the bit depth when shooting in electronic mode. Whether or not this is an issue, I can't say.

The electronics will not be stressed in the least. Most cameras can record full-sensor movies at 60+ fps....  Rolling shutter and other effects should be complete non-issues.

Alen K
Alen K Senior Member • Posts: 1,271
Re: Electronic shutter on the Sony A7R II

Jeffry7 wrote:

Alen K wrote:

Jeffry7 wrote:

I have run hundreds of frames of photographic stills through autostakkert. My biggest single stack was just shy of 700 frames.

It didn't have a problem with this.

Good to know. How big were the frames?

After cropping with PIPP, they were 2400X2400. The files where around 13MB.

Ah, they were cropped first. That checks with what I have heard elsewhere.

OP Igor Sotelo Regular Member • Posts: 461
Re: Electronic shutter on the Sony A7R II

Greg Campbell wrote:

Silent shutter is a wonderful thing when shooting lots of images. Time-lapse, lightning, short exposure astro, etc. The reduction in vibration and - yes - mechanical wear and tear is worthwhile. (I honestly can't fathom the crowd that argue against the increased longevity. I guess they see cameras as trivial and disposable?!) The only drawback is that some cameras drop the bit depth when shooting in electronic mode. Whether or not this is an issue, I can't say.

The electronics will not be stressed in the least. Most cameras can record full-sensor movies at 60+ fps.... Rolling shutter and other effects should be complete non-issues.

I agree, it doesn't make sense to use the DSLR for something they weren't designed to do, to take thousand pictures at every shot or very high quality videos. The 5Ds, 6D and D800 only shot 1920x1080 over full frame. The Df doesn't shot video at all.

The A7R II shots 4K in super 35 and full frame. Timelapse, would bring better quality and can be done at 24 or 30 fps rate up to 990 frames. And won't damage the camera over time.

The advantage is that with just the mount/tripod, could use the photo equipment to start. But from what I have seen so far, one also needs a guiding scope, a guiding camera and a controller.

If I go with a dedicated planetary/DSO camera, I will have to focus AF lenses manually, which may be a problem because of the short throw, so would need a telescope too. But maybe adapted AF lenses would work?

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Guido FORRIER Senior Member • Posts: 1,837
Re: Electronic shutter on the Sony A7R II

I use a Sony A7R II and I shoot a lot in electronic mode but not for astro. Electronic mode does not work in bulb mode . Not a problem because is use mostly ( or I did shoot mostly when the skies were clear  , a long time ago ) 5 to 10 minutes exposure . This wil not harm the shutter .

Guido

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Tristimulus Veteran Member • Posts: 7,555
Re: Electronic shutter on the Sony A7R II
1

Guido FORRIER wrote:

I use a Sony A7R II and I shoot a lot in electronic mode but not for astro. Electronic mode does not work in bulb mode . Not a problem because is use mostly ( or I did shoot mostly when the skies were clear , a long time ago ) 5 to 10 minutes exposure . This wil not harm the shutter .

Guido

My strategy is lots of 30 sec exposures and silent shutter. Have some light pollution so using longer sub exposures do not add anything - besides some added blur by turbulence.

And no guiding needed! Grab and go. Why complicate things with looong exposures just because the mindset is stuck in the needs of the CCD era. We are into CMOS now.

Modern image sensors have very low read noise so that is a non issue in my case. Read noise is way less than the noise from the light pollution anyway. Have tried this out.

If the site is dark then go for longer sub exposures.

Below: M31 and lots of 30 sec sub exposures.

OP Igor Sotelo Regular Member • Posts: 461
Re: Electronic shutter on the Sony A7R II

Trollmannx wrote:

Guido FORRIER wrote:

I use a Sony A7R II and I shoot a lot in electronic mode but not for astro. Electronic mode does not work in bulb mode . Not a problem because is use mostly ( or I did shoot mostly when the skies were clear , a long time ago ) 5 to 10 minutes exposure . This wil not harm the shutter .

Guido

My strategy is lots of 30 sec exposures and silent shutter. Have some light pollution so using longer sub exposures do not add anything - besides some added blur by turbulence.

And no guiding needed! Grab and go. Why complicate things with looong exposures just because the mindset is stuck in the needs of the CCD era. We are into CMOS now.

Modern image sensors have very low read noise so that is a non issue in my case. Read noise is way less than the noise from the light pollution anyway. Have tried this out.

If the site is dark then go for longer sub exposures.

Below: M31 and lots of 30 sec sub exposures.

Interesting point. I have some questions.

To go over 1000mm (which will be able to do with 500mm f/4 once I get a 2x TC), does it makes sense to think about an edge HD 11” SC telescope, that’s around 2800mm f/10. For planetary photography, will 3x increase in FL mean much?

Since the 11” edge HD can have the secondary mirror unscrew and one can put there a Starizona Hyperstar 4 HD lens, which can 35mm in diameter image to use on something like the Sony QX1 without any obstructions or much vignetting, resulting in a 540mm f/1.9 telescope (maybe around 670mm on a APS-C sensor). Will that be useful for deep space over using 300mm 2.8 or 500mm 4.0 on full frame?

Finally, does it makes sense to pickup some very small CMOS sensors to gain 5x FL in the case of Celestron’s 10MP sensor or around 7x for some ZWO 2.1MP sensors. Will I be able to get good photos of Uranus or Neptune? Can one do the same by just cropping from a 42MP A7R II sensor and avoid focusing problems?

Thx

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Guido FORRIER Senior Member • Posts: 1,837
Re: Electronic shutter on the Sony A7R II

my problem with 30 sec. subs is that for 6 hours I need 720 exposures , and that is a lot to handle for my or your  computer . but it is doable .

Guido

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Tristimulus Veteran Member • Posts: 7,555
Re: Electronic shutter on the Sony A7R II
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Guido FORRIER wrote:

my problem with 30 sec. subs is that for 6 hours I need 720 exposures , and that is a lot to handle for my or your computer . but it is doable .

Guido

Hmmmmm. Did you not mention bad weather in another post? If so plenty of low quality overcast time to let the computer churn trough the images.:-D

My typical exposures are 8x30sec for getting an overview when searching for new targets. This is done around full moon.

64x30sec for a typical portrait of brighter objects. 128x30sec and 256x30sec for fainter stuff. Have lots of bad weather here so 64x30sec is kind of standard.

Love 2^n. 

Guido FORRIER Senior Member • Posts: 1,837
Re: Electronic shutter on the Sony A7R II

bad weather : I just saw the forecast : no clear skies in sight !

I only want clear skies , no or less  light pollution , low humidity , low air pollution , no turbulence ... so the higher and colder the better .

Sometimes I can find these situations when we travel with our camper to the Eifel ? Black Forest , the Auvergne (France) , Alps , Pyrenees , rural areas in Spain .... BUT now when I have better equipment and skills , I can not travel and weather stays bad .

I wonder why I have this hobby .

Guido

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Tristimulus Veteran Member • Posts: 7,555
Re: Electronic shutter on the Sony A7R II
1

Igor Sotelo wrote:

Trollmannx wrote:

Guido FORRIER wrote:

I use a Sony A7R II and I shoot a lot in electronic mode but not for astro. Electronic mode does not work in bulb mode . Not a problem because is use mostly ( or I did shoot mostly when the skies were clear , a long time ago ) 5 to 10 minutes exposure . This wil not harm the shutter .

Guido

My strategy is lots of 30 sec exposures and silent shutter. Have some light pollution so using longer sub exposures do not add anything - besides some added blur by turbulence.

And no guiding needed! Grab and go. Why complicate things with looong exposures just because the mindset is stuck in the needs of the CCD era. We are into CMOS now.

Modern image sensors have very low read noise so that is a non issue in my case. Read noise is way less than the noise from the light pollution anyway. Have tried this out.

If the site is dark then go for longer sub exposures.

Below: M31 and lots of 30 sec sub exposures.

Interesting point. I have some questions.

To go over 1000mm (which will be able to do with 500mm f/4 once I get a 2x TC), does it makes sense to think about an edge HD 11” SC telescope, that’s around 2800mm f/10.

At my location the 530mm focal lenght is overkill for deep sky. Turbulent air always blur the images so my plate scale of 1.5 arc seconds per pixel cover it all.

For planetary photography, will 3x increase in FL mean much?

It will increase the focal lenght. But also the effects of the atmosphere.

I use my little telescope (106/530-5) at f/15 (3x barlow) to image the moon and the planets. With my planetary video camera which has 2.4 micron pixels the system is diffraction limited. No gain by using longer focal lenghts.

The size of the planets are pretty small, but that is the size of my sky! Happy with that.

Example - the moon and a humble 1590mm focal lenght (take a look at full size):

Since the 11” edge HD can have the secondary mirror unscrew and one can put there a Starizona Hyperstar 4 HD lens, which can 35mm in diameter image to use on something like the Sony QX1 without any obstructions or much vignetting, resulting in a 540mm f/1.9 telescope (maybe around 670mm on a APS-C sensor). Will that be useful for deep space over using 300mm 2.8 or 500mm 4.0 on full frame?

Some like the Hyperstar. Quite a few complain because collimation is difficult.

My cup of tea is small, handy and easy. Big dreams are easily crushed. Small dreams remain robust and last forever.

Have a small astro shed. Am into business within 10 minutes including taking the flats. Unpacking takes hardly 5 minutes. That is astronomy heaven to me (ignoring the fact that the weather is usually lousy here).

Finally, does it makes sense to pickup some very small CMOS sensors to gain 5x FL in the case of Celestron’s 10MP sensor or around 7x for some ZWO 2.1MP sensors.

The smaller image sensors do not extend the focal lenght of the telescope. They just crop the image. Plate scale is determined by the actual focal lenght anyway.

Make the system diffraction limited. No more. That is about f/15 for 2.4 micron pixels.

Longer focal lenghts are a waste. Why go for empty magnification just to get a larger but more blurry image with absolutely no added detail?

Will I be able to get good photos of Uranus or Neptune? Can one do the same by just cropping from a 42MP A7R II sensor and avoid focusing problems?

Shorter focal lenghts and tiny pixels have the upper hand. Why image at f/40 when f/15 can do the trick? And why use a camera not quite up to the job at hand when a small video camera will easily nail it?

The end result depends upon the atmospheric conditions at your site. The atmosphere, not the telescope, is usually the limiting factor when using mid sized or large telescopes. We can not beat nature.

Thx

zurubi Contributing Member • Posts: 547
Re: Electronic shutter on the Sony A7R II

I shoot wit hSony and Fuji. Some cameras downgrade from 14 bits to 12 bits when choosing the electronic (silent) shutter. My Fuji does. The a7r3 doesn't. I quickly googled the a7r2 and seems like it does.

Losing 2 bits is really bad for night photography so I'd avoid it.

If you want to be sure, shoot using the different shutter options and open the file, for example, in rawdigger.

Igal
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