After recently obtaining a powermate 5x from another iceinspacer...
I have posted some pics here to show the difference in image quality i observe.
i realise the pics ain't the best, but as a comparison i think they work quite well....
For photo 1:
The powermate is bolted to a 8"dob and a Canon 7d in video mode.
For photo 2:
I used a GSO 15mm plossl in an eyepiece projection adapter,
which ended up showing jupiter at around the same apparent size.
All other settings were the same, except i did have to up the ISO for the plossl shot, as it was just too dim. The were shot at about 3am this morning within minutes of each other, so the seeing should not have changed that much.
Each photo is the result of around 5000 frames,
sorted and cropped in PIPP, stacked in autostakkert, and final sharpening done in registax.
My two observations:
1.) Powermate resulted in a much brighter image
2.) Powermate was much easier to focus.
The photo with barlow has more definition than the photo by projection of eyepiece. You see more details.
Barlow change the focal length. eyepiece cause amplification.
With change of focal length of telescope you have an increase of resolution. Aparent amplification.
For astrophotography with projection toward sensor of a camera the image from barlow (with good quality or small spheric distortion) will have always better definition than eyepieces projection.
note: barlow is a negative lens; don't amplify. Mirror (spheric or parabolic as used in telescopes) don't amplify, it reduces the image. Sensor of camera isn't lens, therefore it doesn't amplify. The aparent amplfiication of barlows is actually increment in resolution.
Use of barlow has limitation by refraction. Barlow 5x needs good seeing to produce good results. Because this a 2x , 2.5x or 3x is more useful.
