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dark current noise

Started Jan 5, 2016 | Discussions thread
OP alexisgreat Veteran Member • Posts: 6,459
Re: Home-made "slim" T-Ring adapter for Micro 4/3

Astrotripper wrote:

alexisgreat wrote:

Astrotripper wrote:

alexisgreat wrote:

Astrotripper wrote:

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.

Thanks! So you have a MAK too?

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

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!

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).

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

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

Wow did you use a mylar solar filter?

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).

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.

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.)

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).

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.

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.

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.

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.

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

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

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.

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

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.

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.

 alexisgreat's gear list:alexisgreat's gear list
Olympus C-7070 Wide Zoom Fujifilm FinePix HS20 EXR Fujifilm FinePix HS50 EXR Olympus E-520 Olympus PEN E-PL6 +3 more
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