Here is a stack of two 3 minute shots from 16/6 taken with my 20D piggybacked on the little ETX90. I got the focus off a bit so it is not a sharp as I would like but I am happy nonetheless. Shot at iso 1600, 18mm and F7, stacked in Registax levels and tweaks in PS Elements, noise removal with Neat Image.
Very impressive shot John, you've inspired me to have a go myself. Did you use the standard 18-55 lens, how did you fire the shutter (cable or timer), did you use the mirror lockup facility and did you use the long time exposure noise reduction option??
Yup that was with the kit 18-55 lens stopped down to F7 to reduce abberation (with only partial success as you will see if you look in the corners of the image) , I used the TC80-N3 timer remote control (but you could use your laptop to do the same with a suitable cable), I used mirror lock and in camera noise reduction.
Thanks to all for your positive comments I must say I am having great fun with the wide field shots but would love to go deeper - I just cannot mange to expose for long enough with the ETX90 at prime. I am seriously looking for a better mount now ...
fantastic image! I never knew the ETX90 could do that! I had one but got rid of it because the imaging gear I had was far to heavy for it. Well done John!!
Mike you are correct this is a piggyback shot. The ETX90 is very limited as an astrophotography platform piggy back gives the best results, even then I am limited to the shorter focal lenghts if I want to shoot long exposures.
I can use 15s at prime or 60s at 400mm however this will result in 50%+ failure rates, this reduces the available detail in the images and means I have to stack many images to get a result...and they are not good. I have an M42 taken at prime for comparison - I have not posted any deep DSO images taken through the ETX90 for good reason - I haven't taken any - yet. I am working on a few projects though and I think there is some more milage in this little gem for me to explore....
Had another go at the Milky Way and got the focus right...
Had another go at this shot last night this is a stack of 8x2mins at iso 1600 and f11, other details as for previous image. The original is quite a lot shaper hope it holds up after compression....
Magnificent shot John! Very sharp! You should take a couple along the length of the milky way and make a mosaic of them!
Don't forget you can always upload your hi-res shots to some off-site webspace and provide a link to them, if the compression is doing too much damage.
Nice Milky way pic there JohnH. Youre lucky with the D20 too, I dont think they get the "amp glow" on right hand side of images with long exposures as it turns off the amplifier when taking images.
Thats a nice ETX shot of M42 as well the tracking and focus perfect the fainter stars round pinpoints. Good right across the field too, a nice little scope.
Scott
I tried to take a wide field shot of the milky way running through Cygnus. But even though I was in a semi dark site my images didn't really show much at all. IU was using the 300D standard 18-55mm lens (at 18mm) I took 6 images at various ISO's at around 3 minutes each.
Thanks very much for the kind comments it really gives me a thrill to be able to grab these images from the back yard I am really blown away by what this camera can do. I was very pleased with this image, and yes, I really ought to put the high res image somewhere, just have to sort out my ISP/hosting.
Mike, I think I will have a go at your mosaic suggestion, perhaps at 55mm to start with, should be able to get better detail that way. Any suggestions as to how to put it together? I have never done a mosaic shot - I assume I will have to use identical conditions for each frame? I only have the software that came with the camera, photostich, I am not sure if it is any good, all feedback or suggestions welcome.
This will mean I will have to build the dew heater I bought the bits for the other week, currently I get fogged out after about 1 hr, I had another 7 shots from this run ruined by dew ....
Depending on how each shot comes out you might be able to use "autostitch" to merge them - it's THE best program i've found for creating mosaics. Works perfectly on terrestrial and lunar shots, not sure how it will go with milkyway shots and thousands of stars, but it's worth a shot.
Otherwise you'll have to manually mangle them, I guess.. but it would make a stunning image.
A peice of software called REGISTAR will to that as well. Basically you give the program 2 or more images and then it automatically looks at the stars in the images and rotates / resizes the images to fit together perfectly.
I've used REGISTAR once and thought that it was an excellent program. The downside is that there isn't a free version available and costs around 100USD.
Don't mix this program up with Registack they are not the same.
![[1ponders]'s Avatar](../vbiis/customavatars/avatar45_9.gif){kind=avatar}
