dark current noise

Astrotripper said:

alexisgreat said:

Astrotripper said:

alexisgreat said:

Astrotripper said:

But I have to warn you, at f/10, even the Moon will require very high ISO to keep the shutter fast enough. As for imaging deep sky objects at long exposures, you definitely could use that focal reducer to get it down to f/6.3.

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Thanks! So you have a MAK too?

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Yeah, I got a SkyWatcher Virtuoso that came with tiny little 90mm MAK that's rather useless. But I also got a slightly larger 102mm one that I could actually use to image the moon and sun (with proper solar filter of course). For example something like this:

see it on flickr

or this:

see it on flickr

Astrotripper said:

To complement my 8" SCT, I also have an ETX-90RA, 90mm MAK. I think the E-PL6 may be the only interchangeable lens camera still made that the tabletop equatorial mount of that telescope can handle!

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Well, the problem here will probably be the shutter shock. No idea how your telescope will play along, but that little 90mm MAK I have is so susceptible to shutter shock, that even very fast shutter speeds are useless. It's basically completely useless for astrophotography unless you use fully electronic shutter (or you shoot video for later stacking, but video from Olympus cameras is very bad for this).

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Both are very sharp and detailed! Did you use manual focus?

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Yes, there is no other way with a telescope (not without a computer connected to the setup at least).

Astrotripper said:

Wow did you use a mylar solar filter?

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Don't know what that is. I used a cheap Baader filter that you buy by the sheets. Looks like a piece of aluminium foil. Used it on my telescope (home-made holder made by previous owner of the telescope), my binoculars, photographic lenses and finder scope. There are two types, one for visual observing and one for photography (obviously, you should never look at sun through the thinner, photography version of the filter).

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What you have there is mylar it's also going to serve you well for viewing/taking pictures of solar eclipses. There's a total one from the NW to the SE coming up in August 2017 and then a near total one for the NE in April 2024.

Astrotripper said:

Astrotripper said:

Can I just use the timer with the E-PL6 and avoid shutter shock with the telescope? I set antishock to 1/8 sec since there is no 0 sec option There isn't an electronic shutter either (at least I have not found any option for it.)

Click to expand...

If you scope is anything like mine, then no. There should be no problems with the big one (Nexstar), though (at least I would expect so).

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I think my MAK is like yours, the original mount is very- brittle. I bought some mounting rings for it to attach it to the Nexstar Mount so I think that might help when I move the OTA there. I'm also looking to get a dovetail mount to directly attach the camera to the mount (without a scope) I was told that set up is good enough for 1 minute exposures without significant star trailing. So a bunch of 1 minute exposures could be done that way and then stacked.

Astrotripper said:

Astrotripper said:

Astrotripper said:

Astrotripper said:

I know you said I shouldn't worry about all the junk between the camera and telescope, but should I still definitely leave the correct image diagonal out? The only reason I was thinking of using it is for imaging near the zenith it will rotate the camera 90 degrees so the camera isn't near the base of the mount.

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If the camera can fit there, it's not a problem. That's when that tilting screen fill come in useful. But if it can't fit, than I guess you won't have much choice but to try.

Either way, don't be afraid to experiment. Just try both ways and see how it goes. There's nothing better than first hand experience.

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I bought a customizable lcd protector for the camera that you have to cut to fit the screen (which is good because the screen has a nonstandard aspect ratio) but I see it came with a piece of nylon already attached- should I just leave this on and not use the protector unless the original nylon protecting the lcd falls off? I noticed the touch screen still works.

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Never cared for that stuff, never used such things on anything, even my phone.

Astrotripper said:

I'm still looking for the options for setting the touch screen to only change the focus point rather than also release the shutter

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Not sure how it works on E-PL. On my E-M10, there's a small icon on the left edge of the screen that you can touch to change the mode. If it's not there, I have no idea, read the manual.

Astrotripper said:

and the one for the level gauge- I haven't found either yet.

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Change display mode with Info button, one of those should be level gauge. If not, read the manual to learn if that feature is even there or how to enable it.

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Thanks, I started reaing the included manual and realized it was a "basic manual" and the real manual is on CD (also found a link to it in a search so that might be the best way to do it.) The E-PL6 is supposed to be the first Pen Lite to have a level gauge but I haven't found it in the menu yet, Olympus menus can be pretty overwhelming at times.

--
https://supermanalexthegreat.shutterfly.com/

alexisgreat said:

Astrotripper said:

alexisgreat said:

Can I just use the timer with the E-PL6 and avoid shutter shock with the telescope? I set antishock to 1/8 sec since there is no 0 sec option There isn't an electronic shutter either (at least I have not found any option for it.)

Click to expand...

If you scope is anything like mine, then no. There should be no problems with the big one (Nexstar), though (at least I would expect so).

Click to expand...

I think my MAK is like yours, the original mount is very- brittle. I bought some mounting rings for it to attach it to the Nexstar Mount so I think that might help when I move the OTA there. I'm also looking to get a dovetail mount to directly attach the camera to the mount (without a scope) I was told that set up is good enough for 1 minute exposures without significant star trailing. So a bunch of 1 minute exposures could be done that way and then stacked.

Click to expand...

That's right. I have something like that, only more primitive (Sky-Watcher Virtoso) and I did some astrophotography tests just few days ago. Works pretty well if you don't aim it up too much (it pretty much stops working when pointing directly at zenith, but maybe the one you have behaves better). Anyway, you can take a look at what I came back with here, here and here . All single exposures without any stacking.

Astrotripper said:

alexisgreat said:

Astrotripper said:

alexisgreat said:

Can I just use the timer with the E-PL6 and avoid shutter shock with the telescope? I set antishock to 1/8 sec since there is no 0 sec option There isn't an electronic shutter either (at least I have not found any option for it.)

Click to expand...

If you scope is anything like mine, then no. There should be no problems with the big one (Nexstar), though (at least I would expect so).

Click to expand...

I think my MAK is like yours, the original mount is very- brittle. I bought some mounting rings for it to attach it to the Nexstar Mount so I think that might help when I move the OTA there. I'm also looking to get a dovetail mount to directly attach the camera to the mount (without a scope) I was told that set up is good enough for 1 minute exposures without significant star trailing. So a bunch of 1 minute exposures could be done that way and then stacked.

Click to expand...

That's right. I have something like that, only more primitive (Sky-Watcher Virtoso) and I did some astrophotography tests just few days ago. Works pretty well if you don't aim it up too much (it pretty much stops working when pointing directly at zenith, but maybe the one you have behaves better). Anyway, you can take a look at what I came back with here, here and here . All single exposures without any stacking.

Click to expand...

The one I have you can move up and down along the dovetail to adjust for viewing along the zenith and this is where the tilting LCD might come in handy (either that or I'll try a diagonal.)

Wow those are spectacular with the EM10! I think you might have captured stars down to mag 13-14 in there (especially the double cluster.) I had a question- was that the actual color of the stars, some of them look very magenta-purplish. One of the settings I was looking at was something which makes the WB cast "warm" at higher ISO, should I leave it at that or set it to "Normal" so there is no warm WB cast at higher ISO. I was a bit confused as to what this setting actually does, but maybe it will make star colors come out better?

--
https://supermanalexthegreat.shutterfly.com/

alexisgreat said:

Wow those are spectacular with the EM10! I think you might have captured stars down to mag 13-14 in there (especially the double cluster.)

Click to expand...

Yes, at longer exposures, those fainter stars really pop out. Stacking would allow to bring more of them out of the depths of space

alexisgreat said:

I had a question- was that the actual color of the stars, some of them look very magenta-purplish.

Click to expand...

See my reply to yyr in another thread here

alexisgreat said:

One of the settings I was looking at was something which makes the WB cast "warm" at higher ISO, should I leave it at that or set it to "Normal" so there is no warm WB cast at higher ISO. I was a bit confused as to what this setting actually does, but maybe it will make star colors come out better?

Click to expand...

It does not matter when dealing with RAW files.

Astrotripper said:

alexisgreat said:

Wow those are spectacular with the EM10! I think you might have captured stars down to mag 13-14 in there (especially the double cluster.)

Click to expand...

Yes, at longer exposures, those fainter stars really pop out. Stacking would allow to bring more of them out of the depths of space

Astrotripper said:

I had a question- was that the actual color of the stars, some of them look very magenta-purplish.

Click to expand...

See my reply to yyr in another thread here

Astrotripper said:

One of the settings I was looking at was something which makes the WB cast "warm" at higher ISO, should I leave it at that or set it to "Normal" so there is no warm WB cast at higher ISO. I was a bit confused as to what this setting actually does, but maybe it will make star colors come out better?

Click to expand...

It does not matter when dealing with RAW files.

Click to expand...

Thanks, with my telescope I was able to see stars down to 14th mag, so you have the equivalent of an 8" telescope there do you think you might have gotten stars even dimmer than that (mag 15-17?)

I did some imaging with the E-PL6 last night and this morning and made the mistake of doing it handheld, the stars turned out quite blurry. I had been using my E-520 at ISO 1600 15 sec exposures handheld at 14mm and there was no image blur with my arms propped on a wall, but then again the E-520 is a heavier camera. Also I believe the pen lites' IS turns off at shutter speeds slower than 2 seconds doesn't it?

This may not be the right place to ask, but it seems like a place to start. I was trying some long-exposure night sky time-lapse photography the other night, with my E-M5ii, running firmware 1.3, I think.

I tried exposure times of 4 seconds to 20 seconds. I was using electronic (silent) shutter, the heart icon, to reduce the mechanical shutter wear during time-lapse. I had Noise Reduction (?) disabled, the one that turns off dark-frame subtraction.

I was surprised to see that, with even a 4-second exposure, using silent shutter, the camera apparently did a dark-frame subtraction anyhow, even though it was disabled, as far as I could tell.

When I set the shutter to anti-shock with mechanical shutter, the dark-frame subtraction didn't happen, and I could shoot again immediately after the exposure finished.

Is this how it works on other Olympus cameras, is this "normal"? Or did I just miss something?

I knew silent shutter could introduce banding, and might reduce bit depth. But I didn't realize it apparently introduced a requirement for dark-frame subtraction for multi-second exposures.

RedOctobyr said:

I was surprised to see that, with even a 4-second exposure, using silent shutter, the camera apparently did a dark-frame subtraction anyhow, even though it was disabled, as far as I could tell.

When I set the shutter to anti-shock with mechanical shutter, the dark-frame subtraction didn't happen, and I could shoot again immediately after the exposure finished.

Is this how it works on other Olympus cameras, is this "normal"? Or did I just miss something?

Click to expand...

I think I figured this out. While trying to do something else on the camera, I noticed a setting specifically for silent shutter Noise Reduction.

Go to Shooting Menu 2, Anti-Shock/Silent, then Noise Reduction (heart icon). It had been set to Auto. When I set it to Off, the automatic dark-frame subtraction in silent shutter mode stopped.

With silent shutter Noise Reduction set to Auto, a 4-second exposure in silent shutter mode would start with a mechanical shutter sound, and would include a 4-second dark frame subtraction at the end. This happened even with the "overall" Noise Reduction (Gear E) set to Off.

With silent shutter Noise Reduction set to Off, a 4-second exposure in silent shutter mode started silently, and did not include a dark frame subtraction. I could shoot again immediately.

I don't know why Noise Reduction settings are partially found in Gear E, and partially in Shooting Menu 2, but at least now I know how to change this

RedOctobyr said:

RedOctobyr said:

I was surprised to see that, with even a 4-second exposure, using silent shutter, the camera apparently did a dark-frame subtraction anyhow, even though it was disabled, as far as I could tell.

When I set the shutter to anti-shock with mechanical shutter, the dark-frame subtraction didn't happen, and I could shoot again immediately after the exposure finished.

Is this how it works on other Olympus cameras, is this "normal"? Or did I just miss something?

Click to expand...

I think I figured this out. While trying to do something else on the camera, I noticed a setting specifically for silent shutter Noise Reduction.

Go to Shooting Menu 2, Anti-Shock/Silent, then Noise Reduction (heart icon). It had been set to Auto. When I set it to Off, the automatic dark-frame subtraction in silent shutter mode stopped.

With silent shutter Noise Reduction set to Auto, a 4-second exposure in silent shutter mode would start with a mechanical shutter sound, and would include a 4-second dark frame subtraction at the end. This happened even with the "overall" Noise Reduction (Gear E) set to Off.

With silent shutter Noise Reduction set to Off, a 4-second exposure in silent shutter mode started silently, and did not include a dark frame subtraction. I could shoot again immediately.

I don't know why Noise Reduction settings are partially found in Gear E, and partially in Shooting Menu 2, but at least now I know how to change this

Click to expand...

Wow, yet more complexity! I wonder why the electronic shutter NR has to be different from the regular one?