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I have a Canon EOS 1200D (Rebel T5) and a reflector telescope, and I want to take some photos of Jupiter with them.

If I use burst mode, camera starts moving its mechanical parts: the mirror, or the shutter, or both. I don't know exactly.

This produce a lot of vibrations on the telescope, thus making motion blur.

Even if I lock the mirror up, and display image on the screen, when I press the shutter button, it stats moving some mechanical parts and producing vibrations.

How can I avoid that? Is there a way to prevent any movement of mechanical parts to take a burst?

vsis
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    What shutter speeds are you using? – OnBreak. Apr 04 '19 at 16:20
  • Assuming your camera features Live View shooting, look for Silent LV Mode in the menu. Take a look at this question that I asked a little while ago about a pretty similar behavior on my Canon 80D. In particular, look at the discussion in the comments between bogl and me. This might help with your issue. Although I'm not using burst mode, so I don't know if this will resolve it for you. – Gern Blanston Apr 04 '19 at 16:25
  • I don't think the xx00D models have 'Silent LV' mode. I could be woefully out of date, though, as I haven't looked at one in years. – Michael C Apr 04 '19 at 17:16

3 Answers3

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In theory, live view mode should ensure the mirror doesn't flip, if you don't use quick mode autofocus.

In practice, though, your camera is a very cheap one, that has probably an integrated shutter/mirror motor, so I assume the mirror actuates the same time the shutter actuates. So, if you use a burst, unfortunately the mirror probably actuates between images in the burst.

Sorry I don't have a source stating the integration of shutter/mirror motor for this particular camera, but at least https://www.lmscope.com/en/Digitalkamera_Vibrationen_en.html says about cheap cameras:

Lower priced SLR cameras generally do not have separate motors that drive the mirror and the shutter. If the shutter is operated in Live View mode, the mirror flips down and then up again. All this flipping shakes the camera and thus causes (sometimes significant) vibrations that may seriously compromise the image quality. To reduce the impact of mirror slap, most models come equipped with a special function called mirror lock-up (mirror pre-release). When the mirror lock-up function is enabled, the mirror is flipped up well before the shutter opens (a time interval between 2 and 8 seconds can be selected). This short pause allows the mirror-induced mechanical vibrations to die down before exposing the film so that they do not affect the image quality.

Edit: now I found the quote: http://krebsmicro.com/Canon_EFSC/index.html

With the 450D, 500D and 1000D, the mirror drops after the exposure ends in a non-flash situation during Live View. With the 40D, 50D, 5D Mark II and 7D, the mirror does not drop in a non-flash Live View situation except when the user executes Quick Mode AF. The sequencing difference is due to the fact that the Rebel cameras use only one motor to control both mirror and shutter operation, whereas the 40D, 50D, 5D Mark II and 7D have two motors for independent control of these functions.
juhist
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  • Oh, I forgot to mention that. Yes, the mirror moves between photos in burst mode. I've found nothing in the menu/settings to prevent that. Probably you're right about the motor. – vsis Apr 04 '19 at 17:11
  • @vsis Does the mirror cycle between frames even when in Live view (and with AF turned off)? – Michael C Apr 04 '19 at 17:14
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    @juhist If the camera is capable of mirror lockup, then it needs separate motors for mirror and shutter. The same is true of any electronically controlled shutter. Your quote is more applicable to many low end film era SLRs than digital bodies. To the best of my knowledge, none of the major manufacturer carried that over into low end digital. Nikon did continue to use the same motor to actuate the mirror and stop down the aperture with the D40 → D3x00 series. But even those models have separate motors for the electronically controlled focal plane shutters. – Michael C Apr 04 '19 at 17:26
  • @MichaelC, Yes. It does it in live view, and no autofocus. I use manual mode to take photos with the telescope. – vsis Apr 04 '19 at 17:51

  • Applicable models: all EOS DSLR cameras except for 1000D, 1100D, 1200D, 1300D.

    https://www.eos-magazine.com/articles/EOS_feature/camera-mirror-lockup.html

    @juhist , you were right. This camera can't lock the mirror. So, it's impossible to take a burst without vibrations.

     – vsis Apr 04 '19 at 20:31
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    @MichaelC True, it's more applicable to film SLRs. I recall seeing some e-mail from a Canon employee about the integrated shutter/mirror motors in cheapest EOS digital cameras, but I can't find it now using a Google search. Should have saved that precious resource. – juhist Apr 05 '19 at 14:59
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If I use burst mode, camera starts moving its mechanical parts: the mirror, or the shutter, or both. I don't know exactly.

Typically, the order of operations is: mirror flips, shutter opens. This is regardless of shooting mode. Using Live View or Mirror Lock-Up changes the rules a bit and takes the mirror flip out of the equation, but the shutter is still there.

Even if I lock the mirror up, and display image on the screen, when I press the shutter button, it stats moving some mechanical parts and producing vibrations.

This is the shutter. If you want to have the absolute minimum amount of vibration, you need to:

  • Use single shot mode
  • Use Mirror Lock Up
  • Have a rock solid tripod
  • Use a remote shutter release
  • Hit the shutter release for the mirror to flip and wait a few seconds
  • Release the shutter to take the shot

If this single pass of the shutter opening and closing is causing you to have camera shake, then you may want to look into a different camera, one that has an electronic shutter instead of a mechanical one.

OnBreak.
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  • Well, currently I'm using single shot mode and shutter timer, until I have a remote shutter control. So I don't have motion blur in that way, although it takes its time to take, for example, 500 photos of Jupiter. Because of that, it would be nice to have more photos in less time, without compromising quality. – vsis Apr 04 '19 at 17:02
  • @Hueco That's what you get for buying superb analog gear! ;) – flolilo Apr 04 '19 at 17:08
  • @vsis Forgive me the question, but why do you need 500 pictures of Jupiter? I would take 1, perhaps two, then check them, and if they are good enough, I would stop (at least until Jupiter and/or its atmosphere had sufficient time to move around a bit). To me, making 500 (or even 20, for that matter) roughly identical shots of some (roughly) inanimate object seems like overkill in post-production. – flolilo Apr 04 '19 at 17:11
  • @flolilo DR is very much an issue in astrophotography if one wants to preserve the different colors of different stars. – Michael C Apr 04 '19 at 17:11
  • @MichaelC Sure, but as far as I understand it, GES only compromises DR a bit, so I think that with a recent camera with a fairly good sensor, this should be the least of concerns. – flolilo Apr 04 '19 at 17:14
  • What is "GES" ? – Michael C Apr 04 '19 at 17:17
  • @flolilo for lucky imaging. I can use video for that. But I'm not getting the resolution I want. I belive I'll get better results with raw photos, instead of video. Even if I get less frames. – vsis Apr 04 '19 at 17:20
  • @MichaelC Global Electronic Shutter. Sorry, should have explained the abbreviation. – flolilo Apr 04 '19 at 17:20
  • @vsis "Lucky imaging" is based on changing atmospheric conditions often referred to as "seeing." The greater time period your 500 exposures are spread over, the more variation you're likely to see. Taking them in burst mode in the shortest possible time will reduce the amount of variability that you are seeking. – Michael C Apr 04 '19 at 17:34
  • @flolilo Any method that keeps the sensor energized almost constantly will produce more heat that will certainly affect DR significantly as the length of the session increases. Any process that only energizes the sensor for short periods when exposures are actually being made and allows the sensor to cool between exposures will heat the sensor more slowly over a long session. – Michael C Apr 04 '19 at 17:37
  • @MichaelC, Oh, I see. I'll stick to take photos during an hour or two. Thank you. – vsis Apr 04 '19 at 17:42
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    @vsis ah, your question wasn't clear to me before. So, you are needing to take how many images within what sort of timeframe? – OnBreak. Apr 04 '19 at 17:42
  • @Hueco I thought a few hundreds in a few minutes, or something like that. But now I believe MichaelC is right. It's not a good idea to shorten the time between photos. – vsis Apr 04 '19 at 17:57
  • @vsis yes and no. It’s a very interesting question. If the assumption is: the more photos the better, then the question becomes: what process allows for the most photos in the shortest time while contending with changing atmospheric conditions and sensor heat? That’s a pretty cool question. – OnBreak. Apr 04 '19 at 18:52
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    @Hueco The probability is that the longer period over which the images are spread, the greater variation in atmospheric conditions will be observed. In the case of "lucky imaging", the goal is to capture as much variation as possible and then use only the frames when the "seeing" was best. It's also the case that if the sensor is not constantly energized (such as in Live View), then the longer the interval between each exposure, the cooler the sensor will be by the 500th frame. – Michael C Apr 04 '19 at 19:03
  • @MichaelC unless you got one of these bad boys: http://www.centralds.net/cam/?page_id=12417 – OnBreak. Apr 04 '19 at 19:34
  • @Hueco I can't seem to find the one built on the Rebel T5/1200D – Michael C Apr 04 '19 at 19:57
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    @MichaelC progress sometimes warrants a new camera (says the guy with a 4x5)...but yea, the active cooling need seems to be even more niche than the IR need (a-la lifepixel). So niche that the specialization of such images is left to those willing to spend on the applicable tech. – OnBreak. Apr 04 '19 at 20:19
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I'm reading your question about the camera, but I'm also reading why you want this (to image Jupiter).

First, to address your direct question on vibration with the 1200D:

The 1200D lacks "mirror lock-up" mode. This is the traditional way to eliminate vibrations caused by mirror-slap. You would have to use live-view mode to eliminate mirror-slap with this camera.

Next, to address planetary imaging:

However, imaging planets is very different from imaging deep-sky objects (DSOs). DSOs (nebulae, galaxies, etc.) are normally imaged via many long-exposure images which are stacked. Planets use a form of "lucky imaging" in which you capture many frames of video, parse through to find the best frames, and then stack those.

This means that to get good results on planets, you would use video instead of single frames. Ideally this would be uncompressed video frames. The camera should preferably be capable of at least 60 frames per second. And because it's Jupiter (which rotates much faster than any other planet in the solar system) the upper-limit for capture time is about 1 minute worth of data (going beyond that will result in the stacked frames blurring from the rotation -- although there is de-rotation software as WinJupos which does a bit of magic with the images to re-map the pixels for better alignment).

The top planetary imagers are guys like Damian Peach and Christopher Go. Damian has a chapter in the book Lessons by the Masters which details the process.

Check out images at Astrobin (extremely popular website for posting astrophotography): https://www.astrobin.com/search/?q=Jupiter&d=i&t=all

Most astro-imagers post details including equipment used, software, and sometimes the processes. You'll notice that ZWO brand cameras are extremely popular for this sort of work (ZWO cameras have model numbers that begin with "ASI..." such as ASI290MC or ASI120MC-S). The least-expensive is the ASI120MC-S and it's able to capture at 60fps (higher end models are much faster). The trends in which cameras are popular changes over time (past brands have been QHY, Imaging Source, Point Grey, etc.) but you'll also notice if you browse through the best images that it's extremely hard to find anyone who uses a DSLR for this type of imaging.

Atmospheric seeing conditions will distort the image quality (picking a good night to image helps). This is where "lucky imaging" comes in. Software can help analyze the video frames and pick the best frames to stack ... rejecting the rest. AutoStakkert and Register are popular stacking programs (and free) for planetary image stacking (don't use these programs for DSOs).

You can use a DSLR for this (put the camera in video mode), but you'll find it easier to get good results with the dedicated CMOS astro-imaging cameras. (In US Dollars, an ASI120MC-S is around $150 ... which makes it a pretty affordable camera.)

Tim Campbell
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