Camera Labs

i am try to get in to astrophotography and keep getting mixed messages when looking to by a telescope (nexstar 8 ).

that the 40D goes blind when hooked up to a spotter or telescope, well considering the photos i have seen taken with the 40D it does work.

can you explain to me what problems i may incounter when hooking up my 40D to a telescope when it comes to focusing / setting it up

i thank you very much in advance for any help

tpazol

Hi tpazol,

May I offer you a warm welcome to the CameraLabs forums. As you can see I've moved your post into the "Technical and scientific photography" forum as that is where all things astro-photographical ( ) get discussed.

The 40D is a great DSLR for astrophotography though the IR cutoff filter is a little more aggressive than some when it comes to the Hydrogen alpha emission line. They can be modified (Hutech) but that means you have to employ an additional filter for normal photography. Another great resource is Christian Buil's site. He has a nice evaluation of the 40D which you can read here.

The TeleVue site has a great summary of the ways of focussing an image on a sensor which you can read here. Typically, you will need a camera adaptor such as those illustrated here. If your telescope can accept a T-mount accessory then an alternative to the regular camera adaptor is a T-mount adaptor such as the ones here. You may or may not need an extension tube to get the camera to the focal plane.

The best possible accessory once the camera is mounted is a notebook computer so that you can use remote Live View. That makes focussing so much easier and once you are set up you can use the same Canon EOS Utility software to control the camera unless you already have dedicated astro software (MaximDL springs to mind, though I haven't used it).

Have a browse through this section. I've added a few posts of my own but if you want to get really serious have a look at posts by cybermystic.

Bob.

_________________
OM-D E-M5 + ED 12-50mm, H-PS14042E, H-F007014E, L-RS014150E, M.ZUIKO DIGITAL 45mm 1:1.8.
Gitzo GT1541T, Arca-Swiss Z1 DP ball-head.
Astrophotography: TEC 140 'scope, FLI ML16803 camera, ASA DDM60 Pro mount.

thank you very much for the info!
if i can bother you with one more question, ok maybe 2 more questions.

when hooked up to the scope, the 40D in live mode; do any of the adjustments work i.e AV, TV, or M for iso or anything?

do you have a favorite scope for asto photos

thanks

If the camera is using the 'scope optics (as opposed to being piggybacked on top of it and using its own lenses) then Av won't work (the camera can't control aperture). Typically you will use either Tv or M mode and ISO is certainly adjustable. However, given the way DSLR sensors work there is usually little advantage with the 40D in dialling in an ISO greater than 400 except, possibly, to reduce the need for post-processing. It's certainly worth experimenting, however, to find out what works best for you.

One of the nice things about the EOS Utilities is that you can set up a sequence of shots such as 5 x 3 minute exposures each separated by 2 minutes to allow the sensor to cool. You can then cover the lens or the telescope objective and take a similar sequence of dark frames. Programs like IRIS can then be used to combine (stack) the frames. Not a technique you need to worry about initially but it can make a substantial improvement to your images as you get more confident.

With very few exceptions I just piggyback the camera onto my telescope to take advantage of the motor-driven mounting to track the stars so I don't use the telescope optics at all.

Have a look at this Sky Online page for more tips on astrophotography.

Bob.

_________________
OM-D E-M5 + ED 12-50mm, H-PS14042E, H-F007014E, L-RS014150E, M.ZUIKO DIGITAL 45mm 1:1.8.
Gitzo GT1541T, Arca-Swiss Z1 DP ball-head.
Astrophotography: TEC 140 'scope, FLI ML16803 camera, ASA DDM60 Pro mount.

thank you very much, i have learned more from you in 10mins than i have i 3 days of talking to people at the stores that don't know what their talking about lol

what's your favorite scope to use and or do you like the nexstars

.
I just have a small TeleVue "Pronto". I mentioned forum member cybermystic above. His web-site is the New Forest Observatory and if you read his observatory page you can see he uses a Nexstar.

Bob.

_________________
OM-D E-M5 + ED 12-50mm, H-PS14042E, H-F007014E, L-RS014150E, M.ZUIKO DIGITAL 45mm 1:1.8.
Gitzo GT1541T, Arca-Swiss Z1 DP ball-head.
Astrophotography: TEC 140 'scope, FLI ML16803 camera, ASA DDM60 Pro mount.

thank you again, i think i am going to go with the nexstar 5se for my starter scope because of the wedge it already has built in and it seems camera friendly.

i took a few photos tonight with my canon 40D, 70-200 f/2.8 IS.
they turned out ok for my first time but, there was a strange very small purple speck in all the photos in the same spot in all of them, any ideas what that might be. the sky moved but the speck stayed still?????



thank you

todd

Hi Todd,

Sounds like a hot pixel, to me. We all tend to see them on long time exposures but if you see it on more normal work you might want to take the matter up with Canon.

Bob.

_________________
OM-D E-M5 + ED 12-50mm, H-PS14042E, H-F007014E, L-RS014150E, M.ZUIKO DIGITAL 45mm 1:1.8.
Gitzo GT1541T, Arca-Swiss Z1 DP ball-head.
Astrophotography: TEC 140 'scope, FLI ML16803 camera, ASA DDM60 Pro mount.

Thank you again, you have been extremely helpful !


Todd

hello all.

im thinking about getting into astro-photography and i was wondering what would be the entry level telescope where i could start this.

_________________
http://www.shadowsandhighlights.co.uk
55-200mm
60mm macro
50mm prime
18mm-135mm

Hi blackrabbit33,

Welcome to the wonderful world of ever decreasing amounts of spare cash.

Just joking! A lot will depend on what sort of astrophotography you want to do. Unless you are content just to take a few photographs of the Moon or some star trails one critically important piece of kit is a motorised equatorial mounting. For those reading this who are unfamiliar with the term that's sort of mounting has its main axis parallel to the Earth's rotational axis so that when driven at the right speed it tracks the stars.

Astrophotography is a huge but rewarding subject so, rather than write a large essay here, may I suggest that you have a look at Sky & Telescope's excellent Astrophotography guide and then come back to us with whatever questions you have?

Bob.

_________________
OM-D E-M5 + ED 12-50mm, H-PS14042E, H-F007014E, L-RS014150E, M.ZUIKO DIGITAL 45mm 1:1.8.
Gitzo GT1541T, Arca-Swiss Z1 DP ball-head.
Astrophotography: TEC 140 'scope, FLI ML16803 camera, ASA DDM60 Pro mount.

Hi bob

well after last night.
i caught the bug for astro photgraphy. i was taking test shots of the moon free hand with my 70-300mm.

and i loved the shot i got. i've added it to the test pics for the 70-300mm in the lense part of this forum.

anyway i just wanted to find a telescope that i could mount my nikon d40 to do give me great shots of the moon to start me off.

any ideas on telescopes that will do the job. entry level to start.

_________________
http://www.shadowsandhighlights.co.uk
55-200mm
60mm macro
50mm prime
18mm-135mm

Hi blackrabbit33,

As you saw with your 300mm lens, the Moon is quite small which means you either need a telescope with a focal length of at least 1000mm or extra optics to magnify the image. This TeleVue page shows some of the options. TeleVue make some nice kit but it isn't the cheapest. I get the impression that you are UK based so have a look at the Venturescope site for a selection of what's available. I've used this store a few times and if you ring with a question Ninian is very helpful. There are, of course, other UK based stores (Google search) as well as the option of importing from abroad.

You may find it really worthwhile having a look for a local astronomy club. They will be able to offer good advice and you may also get a chance to "try before you buy".

Bob.

_________________
OM-D E-M5 + ED 12-50mm, H-PS14042E, H-F007014E, L-RS014150E, M.ZUIKO DIGITAL 45mm 1:1.8.
Gitzo GT1541T, Arca-Swiss Z1 DP ball-head.
Astrophotography: TEC 140 'scope, FLI ML16803 camera, ASA DDM60 Pro mount.

Hi guys, if you've not already seen it, you might find this page interesting:

http://www.cameralabs.com/reviews/Canon ... aphy.shtml

Hi Gordon thanks for that link
i was playing with my nikon d40 trying to see if it had a live veiw option but i could see anything.was i blind or does it not have one.
just on the hunt for right telescope. i shall email that chap from Bobs helpful links.

_________________
http://www.shadowsandhighlights.co.uk
55-200mm
60mm macro
50mm prime
18mm-135mm