The Astro-Imaging Thread

[LegatusFlagrans]

Some stuff I did a while back with the 16" reflector at Alabama.

NGC 891

NGC 253

[kurja]

On 4/14/2017 at 6:24 PM, munlander1 said:

So to get long exposures, I have to have an hdmi cable. My camera does not have a hdmi port. I think the longest I can do currently is 45 seconds. Currently though I have been using an usb 2 to mini usb b. 

??? Why hdmi?

[munlander1]

5 hours ago, kurja said:

??? Why hdmi?

I tether my camera to my laptop. I run backyard eos. When I attempt to take a bulb exposure it is aborted and says I need an hdmi cable for bulb exposures.

[_Augustus_]

2080 fork ships tomorrow. Looks like I'll have the whole scope done by the end of the month.

Also going to go pick up a film hypersensitization chamber. Going to try some film astrophotography!

Edited April 16, 2017 by _Augustus_

[kurja]

9 hours ago, munlander1 said:

I tether my camera to my laptop. I run backyard eos. When I attempt to take a bulb exposure it is aborted and says I need an hdmi cable for bulb exposures.

That makes no sense to me, external exposure control is done via the usb port. hdmi should be just for streaming live view. We've been doing camera tethering long before there were hdmi ports on anything afterall

edit - just took a look at backyard eos manual, you can take bulb exposures even with a serial cable

Edited April 16, 2017 by kurja

[munlander1]

2 hours ago, kurja said:

That makes no sense to me, external exposure control is done via the usb port. hdmi should be just for streaming live view. We've been doing camera tethering long before there were hdmi ports on anything afterall

edit - just took a look at backyard eos manual, you can take bulb exposures even with a serial cable

Don't know, will take a look at the manual.

[kurja]

12 hours ago, munlander1 said:

Don't know, will take a look at the manual.

On most cameras, even modern digital bodies, electrical shutter trip is really just a short - I have, literally, triggered exposures with a paper clip. I'll be amazed and not in a good way if latest cameras now demand something through hdmi just to trip the shutter

[Green Baron]

I don't think they do. But mine (Nikon D700) limits the max built in shutter time to 30sec. Too short for astro-images. I got me a programmable timer with a cable connector for the cameras proprietary cable plug, so i am independent from a laptop and usb cabling. Am sure such a thing exists for Canon cameras as well.

... quick search: yes, it does: https://www.learn.usa.canon.com/app/pdfs/quickguides/CDLC_TC-80N3_QuickGuide.pdf

Edit: but maybe you can get away with half the price when using a third party thing ...

Edited April 17, 2017 by Green Baron

[kurja]

27 minutes ago, Green Baron said:

I don't think they do. But mine (Nikon D700) limits the max built in shutter time to 30sec. Too short for astro-images. I got me a programmable timer with a cable connector for the cameras proprietary cable plug, so i am independent from a laptop and usb cabling. Am sure such a thing exists for Canon cameras as well.

... quick search: yes, it does: https://www.learn.usa.canon.com/app/pdfs/quickguides/CDLC_TC-80N3_QuickGuide.pdf

Edit: but maybe you can get away with half the price when using a third party thing ...

Sure, You can exceed the 30sec limit without a timer as well, just keep the shutter button down as long as you like, on the camera or a remote. Although if he's using tethering software then it should control the shutter.

[Green Baron]

Of course, there is the "bulb" setting. But that's a little impractical on a tripod/mount, for that and for being independent from a laptop i got the cable timer.

I freely admit i would be distracted when trying this (20*240sec e.g.) manually, and i only used this setup with the timer once until now (for andromeda over in the lounge thread). And my fat finger wouldn't really calm the situation :-)

But what exactly was @munlander1's question ? The kind of cable ? Most probably a usb if controlling the camera from the laptop. If controlling from a timer then no cabling or laptop is needed. How to do really long exposures ? Laptop or external timer if the built in timer doesn't allow for minute-long exposures.

 

 

[munlander1]

Was wondering how to get long exposures. So what duel mode should I be using? With this external timer could you set up several exposures? How much do these cost?

I was (and still am) wondering if there was a cable that would alleviate the error backyard eos was spitting out. I do use a usb cord to tether it.

[PakledHostage]

2 hours ago, munlander1 said:

I was (and still am) wondering if there was a cable that would alleviate the error backyard eos was spitting out. I do use a usb cord to tether it.

While astrophotography isn't really my forte, I do occasionally play at being a photographer. I use a TriggerTrap dongle to control my Canon EOS camera via the audio jack on my phone. The app allows you to configure and execute bulb exposures of arbitrary lengths (among other things). Unfortunately TriggerTrap has gone out of business but you might still be able to find their stuff somewhere with the help of Google.

Another option may be to make your own serial dongle according to the instructions on this website: http://www.beskeen.com/projects/dslr_serial/dslr_serial.shtml. 

Edit:

I got the link above from the "Eclipse Orchestrator" website (they make software for automating a series of photos during an eclipse). Another serial shutter release option that they list is this one: http://www.store.shoestringastronomy.com/products_ds.htm. 

My old EOS-M (the original model) can't be triggered remotely even though you can connect to it with Canon's software over USB, but I was able to modify a Canon IR remote so that I could trigger it via an Arduino. That may be yet another option for you?

 

Edited April 17, 2017 by PakledHostage

[_Augustus_]

Picking up the film hypersensitization chamber Thursday! I can't wait!

[kurja]

8 hours ago, munlander1 said:

Was wondering how to get long exposures. So what duel mode should I be using? With this external timer could you set up several exposures? How much do these cost?

I was (and still am) wondering if there was a cable that would alleviate the error backyard eos was spitting out. I do use a usb cord to tether it.

What camera are you using? I was assuming an EOS?

[Green Baron]

12 hours ago, munlander1 said:

Was wondering how to get long exposures. So what duel mode should I be using? With this external timer could you set up several exposures? How much do these cost?

I was (and still am) wondering if there was a cable that would alleviate the error backyard eos was spitting out. I do use a usb cord to tether it.

Duel mode ? No comprendo ... :-)

I can only describe what my timer does (with the ridiculous and untranslatable name Hähnel Giga Pro T II): it has several modes, the most complex is to define a series of m exposures each n seconds long, and do this o times with different pauses between exposures and series of exposures. Exposure time and number of exposures in each series can vary. And all that with three buttons . Always have the manual with you :-) But you can simply tell it to do m exposures, each n seconds long and make a pause of o seconds between each one.

I don't remember the exact price, but i remember i thought twice.

To the error if you could specify ? Spitting eos' in the backyard are harmless if tethered to a long cord ...

[munlander1]

I am using a cannon rebel eos. Will try to get the error tonight.

[_Augustus_]

Got the hypersensitization chamber today. Needs one part replaced, but it works other than that. Even has a bit of gas left.

[Green Baron]

9 hours ago, _Augustus_ said:

Got the hypersensitization chamber today. Needs one part replaced, but it works other than that. Even has a bit of gas left.

It is almost 20 years since i last touched a real film and bathed my hands in chemicals. You have my respect trying that out. Good luck ! :-)

 

[_Augustus_]

3 hours ago, Green Baron said:

It is almost 20 years since i last touched a real film and bathed my hands in chemicals. You have my respect trying that out. Good luck ! :-)

 

I took a photography class last fall. We did mostly digital but we spent some time shooting and developing black and white film - even made our own prints.

IMO it's not very hard, just a bit time-consuming. I am probably going to start out having the film developed at a good local place.

[Green Baron]

Basic b&w processing is not hard at all.

But especially for landscapes it can be made incredibly complicated sophisticated. My favourite b&w photographer, the master of all of them once wrote "Twelve significant photographs in any one year is a good crop !" (Ansel Adams).

Sorry for being ot :-)

Edited April 21, 2017 by Green Baron

[_Augustus_]

Remaining 2080 parts are on the way!!

[PakledHostage]

I took some photos of the Sun this evening; just playing around with exposures and the new solar filter that I bought in advance of this summer's eclipse. The image below is cropped from one of the better ones (it has been cropped from the original 20+ megapixel image but not re-sized).

According to a SOHO image that I found online, the two sunspots at the lower right are 2651 and 2652. The SOHO image did not identify the other one located closer to the limb, to the left of the main ones. What do you suppose causes the waviness of the limb? I don't think it is a lack of sharpness because the sunspots are reasonably sharp? Is it refraction of light in the Sun's atmosphere?

 

[SuperFastJellyfish]

38 minutes ago, PakledHostage said:

I took some photos of the Sun this evening; just playing around with exposures and the new solar filter that I bought in advance of this summer's eclipse. The image below is cropped from one of the better ones (it has been cropped from the original 20+ megapixel image but not re-sized).

According to a SOHO image that I found online, the two sunspots at the lower right are 2651 and 2652. The SOHO image did not identify the other one located closer to the limb, to the left of the main ones. What do you suppose causes the waviness of the limb? I don't think it is a lack of sharpness because the sunspots are reasonably sharp? Is it refraction of light in the Sun's atmosphere?

 

As a guess, the waviness is from looking through Earth's atmosphere, but I'm super amateur.  I'll be in southern Illinois for the solar eclipse.  I don't know what filter to buy for my 8" scope.  I've seen the metallic ones that go for $100+, but I've also heard there is cheap filter paper(like 10 bucks a sheet for my scope's size) that exists that you can just rubber band to the end of the scope.  Any thoughts on that?

[PakledHostage]

17 minutes ago, SuperFastJellyfish said:

I don't know what filter to buy for my 8" scope.  I've seen the metallic ones that go for $100+, but I've also heard there is cheap filter paper(like 10 bucks a sheet for my scope's size) that exists that you can just rubber band to the end of the scope.  Any thoughts on that?

I am using a long camera lens rather than a telescope so my own solution of a threaded camera filter from Thousand Oaks Optical won't work for you. But maybe have a look at what they have to offer for your telescope? They also sell the film that goes into those cardboard eclipse viewing glasses by the square foot so you could use that to make your own filter. 

Edit: 

I'll be viewing the eclipse from Oregon or Idaho, depending on the weather and crowds. I've been playing around with Eclipse Orchestator in preparation, which is why I was out taking photos of the Sun this evening. The practice will help me set the right exposures in my Eclipse Orchestator script. 

Edited April 22, 2017 by PakledHostage

[Green Baron]

2 hours ago, SuperFastJellyfish said:

As a guess, the waviness is from looking through Earth's atmosphere, but I'm super amateur.  I'll be in southern Illinois for the solar eclipse.  I don't know what filter to buy for my 8" scope.  I've seen the metallic ones that go for $100+, but I've also heard there is cheap filter paper(like 10 bucks a sheet for my scope's size) that exists that you can just rubber band to the end of the scope.  Any thoughts on that?

Just shortly there was an extensive discussion on solar fiters in the forum. In short: 100 is too much (riding the wave of the coming eclipse ;-)) and 10 not enough. If you don't mind a little handwork then take something like this and craft a ring from plywood or so to fix it on your scope. There are different types for visual and photographical.

Buy it now, it*s likely to be sold out in summer ;-)