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Esteemed Contributor
Posts: 3,047
Registered: ‎06-11-2013

Re: Astrophotography - Tips and tricks please.

It's tough when the sky doesn't cooperate with steady seeing.

You can buy a 15' tethering cable. Mine was less than $10 (there are vendors who charge $30-40 for one.) Search for a 15' USB type A male to mini-b and you should find several options.

Have fun!
Tim Campbell
5D III, 5D IV, 60Da
Frequent Contributor
Posts: 102
Registered: ‎06-10-2015

Re: Astrophotography - Tips and tricks please.

Yes but it was my fault mainly as I was trying to observe right after sunset so the atmosphere was really turbulent because of the daytime heat still rising.  I have the next couple of days off and I'm on vacation starting next Wednesday so I can stay up late to let the atmosphere settle down. 

 

Also, I let my kids use my scope a while back (they set it up and put it away, I was not there) and I think they may have done something to the focuser.  I have a lot more mirror shift that I used to have and very little movement of the focus knob to fine tune the object before going out of focus completely.  Not to mention the old girl is almost 20 years old.  I think I'll have to send it in and have it looked at unless I can find some instruction on how to take it apart if it doesn't need any special tools or alignment fixtures to keep the mirror straight. I'm an engineer that works on robots so I'm pretty good with tools and such. I've also built a few telescopes in the past.  This was the first commercial scope I've ever bought.  I've searched for a service manual for it but so far cannot find it on the net.

Esteemed Contributor
Posts: 3,047
Registered: ‎06-11-2013

Re: Astrophotography - Tips and tricks please.

I just did a Google search for "Meade 2080 manual" and this hit pops up:

 

http://www.cise.ufl.edu/~jnw/meade2080-2120manual.pdf

 

It does appear to be the full manaul.  I couldn't find the manual at the Meade website.

 

As for the mirror shift... from time to time, owners suggest running the focuser all the forward (turn it counter-clockwise until you feel it stop), then run the focuser all the way backward (clockwise until it stops).  That helps re-spread the lubricant. 

 

Also, you'll noitce more image shift using a higher power (low focal length) eyepiece than you will using a low-power (high focal length eyepiece) -- just because of the increased magnification.

 

If you have scope questions, you might want to join the users group at the Yahoo Groups website:

 

https://groups.yahoo.com/neo/groups/Meade_2080/info

 

I'm in the Yahoo Group for several telescopes I either currently own or previously owned (LX200GPS, Meade ETX Owners, ETX-LS, and LuntSolar groups and find them to be great resources when I run into issues or have specific questions.)

 

Tim Campbell
5D III, 5D IV, 60Da
Frequent Contributor
Posts: 102
Registered: ‎06-10-2015

Re: Astrophotography - Tips and tricks please.

I have that manual somwhere at home and also have downloaded it but thanks for the link.  I was looking more for an actual maintenance manual not a user manual.  I did find some stuff on taking apart a Celestron  CAT and the guy who made that writeup said Meades were simular. 

I'll try the your suggested trick.  I can't remember which eye piece I was using at the time.  I think it was my 20mm so it wasn't that high.  I'll be sure to checkout the user groups you mentioned as well. 

Hopefully I'll have a clear sky tonight to see Venus and Jupiter together!!!!

Frequent Contributor
Posts: 102
Registered: ‎06-10-2015

Re: Astrophotography - Tips and tricks please.

So I've finally found some time to take some pictures.  I was out of town for almost a month for work so that got in my way.

I did manage to fix my focus shift problem (before going out of town) that my 2080 was having by taking it apart and finding the grease was all dried out. I did a collimation check with a bright light after reassembling the scope but forgot to fine tune it the other night on a star (forgot) before taking the pictures.  This might explain the slight out of focus look.

I used Cannon Connect on my phone to work the shutter.  That worked out pretty good.  I took this shot right after sunset that is why the background it so blue.  I kind of like it other than it's a bit overexposed (to me anyway)

Here is the picture (.jpg I do have a RAW version)

20150822200833_IMG_0681.JPG

 

Image data:

681 data.JPG

Of course this was in Auto mode with the flash turned off.  I tried to take a pictue of Saturn but could not get the focus right before it dropped behind the trees then I realized I hadn't performed a fine tune collimation adjustment.  While doing that Murphy's Law cropped up and my cameras battery died. 

 

I am going to try again tonight.  Any suggestions on manual settings are greatly apprciated.  It should be a good night of seeing as a cold front came through yesterday and it should be good seeing conditions tonight.

 

Esteemed Contributor
Posts: 3,047
Registered: ‎06-11-2013

Re: Astrophotography - Tips and tricks please.

Nice to see you have things working!

 

As you noticed, it's over-exposed.  But it's easy to get a correct exposure when imaging the moon because it's brightness is consistent (since the Sun is illuminating with a consistent amount of light).  You can use a guideline called the "Loony 11" rule. "Loony" for the moon (a bad play on "Lunar") and "11" because the relationship explained by the rule only works at f/11.

 

That rule says:  If you use f/11, you can set the shutter speed to the inverse of the ISO setting.  

 

Based on this rule, a photographer could use f/11, ISO 100, and 1/100th.  Or ISO 200 and 1/200th, or ISO 400 and 1/400th, etc.

 

But you don't have an f/11 scope... it's an f/10 scope (and telescopes don't have adjustable aperture blades or waterhouse stops) -- so you are 1/3rd stop faster than f/11.  But that means you can just dial the shutter to 1/3rd stop shorter duration of the ISO (that's one click on your shutter speed dial) and you're back in business.

 

So... whereas you could use f/11, ISO 100, and 1/100th sec... you are at f/10, but you could use ISO 100 and 1/125th sec exposure time -- and this would nail the moon for you ... every time!

 

The exposure below was taken using the "Loony 11" rule.

 

Moon

 

The surface of the moon has an "albedo" of .12 -- the "albedo" is the surface reflectivity or you can think of it as the amount of light that is reflected back off the surface expressed as a fraction of the total light.  So .12 means 12% of the light that hits the surface will be reflected back.  This happens to almost exactly match the surface albedo of a "worn aspalt" road (not freshly laid aspalt -- which is darker.)

 

Saturn will be more difficult and capturing Saturn will be easier if you put the camera in "video" mode, reduce the resolution to 640x480, and capture about 30 seconds to perhaps 1 minutes worth of video.  You can then use "Registax" or "AutoStakkert" (both are free programs) to perform image stacking and this will result in a much cleaner image after processing. 

 

There are numerous videos on how to use either program to do planetary imaging.

 

One more thing...  Saturn is very low in the sky (Earth northern axis is pointed toward the sun in summer, but that means our northern axis is pointed away from Saturn.  This puts Saturn low in the sky for northern hemisphere observers at that time of year.)  As a consequence, the atmosphere will distort your view of saturn by acting like a lens or prism.  It will disperse the light  so that the light is starting to split into a rainbow spectrum.  If you look closely at saturn, you'll notice one edge of the planet has a blue fringe on the edge... the opposite side has a red fringe.  This will result in a blurring of the entire object (even if the scope is in perfect focus).  The image processing programs (I know Registax has this feature and I think (but am less certain) that AutoStakkert can do it too)) have the ability to split the image into it's red, green, and blue channels, and then slide them back together again so they converge into a sharper image.  (In the old days when astrophotography was done with film there used to be a prism type device called an "Atmospheric Dispersion Corrector" or "ADC".  You can still buy such a device and a "cheap" one would be about $500.  But thanks to digital imaging technology and image processing software, you can digitally correct for this and do not need to buy an ADC.

 

Tim Campbell
5D III, 5D IV, 60Da
Frequent Contributor
Posts: 102
Registered: ‎06-10-2015

Re: Astrophotography - Tips and tricks please.

Thanks again Tim.  Of course the past few days have been clear up until sunset so I haven't been able to get out again.......go figure.

Esteemed Contributor
Posts: 3,047
Registered: ‎06-11-2013

Re: Astrophotography - Tips and tricks please.

I'm not sure where you live but.... on September 27th (a Sunday) there will be a full lunar eclipse. I'm in the US Eastern time zone and for us the eclipse begins shortly after sunset/moonrise (a full lunar eclipse can only happen at the full moon and on that night the Sunset and Moonrise are pretty much teh same time with the Sun setting in the west as the Moon is rising in the east.

The farther west you are, the more the eclipse will already be happening by the time you see the moonrise (it's ideal to be in the US Eastern time zone).

But... if you live in the right area, that would be a GREAT time to go photograph the moon.
Tim Campbell
5D III, 5D IV, 60Da
Frequent Contributor
Posts: 102
Registered: ‎06-10-2015

Re: Astrophotography - Tips and tricks please.

I live in Virginia and have been looking forward to that event for a while.  Can't wait as I might even be on the coast that weekend!  My parents and brother live on the coast of NC about a block from the beach. 

Esteemed Contributor
Posts: 3,611
Registered: ‎06-25-2014

Re: Astrophotography - Tips and tricks please.


TCampbell wrote:
I'm not sure where you live but.... on September 27th (a Sunday) there will be a full lunar eclipse. I'm in the US Eastern time zone and for us the eclipse begins shortly after sunset/moonrise (a full lunar eclipse can only happen at the full moon and on that night the Sunset and Moonrise are pretty much teh same time with the Sun setting in the west as the Moon is rising in the east.

The farther west you are, the more the eclipse will already be happening by the time you see the moonrise (it's ideal to be in the US Eastern time zone).

But... if you live in the right area, that would be a GREAT time to go photograph the moon.

Thanks for the "heads up", Tim. We too are in the Eastern time zone, not too far from its eastern edge, So I'll definitely watch for it. The only problem is the tradition of clouds for eclipses in New England. I can still remember chasing around central Maine trying (unsuccessfully) to get out from under the clouds at the July 1963 total solar eclipse.

Bob
Boston, Massachusetts USA
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