ZWO ASI 2600MM-PRO or QHY268M
31 members have voted
1. Poll: For those people definitely buying OR thinking about getting one of the above new cameras due to be delivered early 2021
ZWO ASI 2600MM - ORDERED ALREADY
ZWO ASI 2600MM - Will Definitely Buy
ZWO ASI 2600MM - I would like this camera
QHY268M - ORDERED ALREADY
QHY268M - Will Definitely Buy
QHY268M - I would like this camera
This poll is closed to new votes
Recently Browsing 0 members
No registered users viewing this page.
Hi all, I tried my takahashi reducer 0.73x (CR version) for the first time with my FSQ85.
I can see a distortion problem but I'm struggling to understand the reasons. you can see it happens before the meridian flip and also after, in the exact same ccd area (QHY268M APS-C sensor).
I'm pretty sure the reducer 0.73 should be able to cover an APS-C sensor without issues.
The right part of the image looks like my sensor is too close to the reducer, with stars pointing towards the centre.
but why the problem isn't mirrored on the left part?
single exposure 60s, some zoom-in.... (full pictures attached)
upper right corner
lower right corner
thanks for any input!
Can I pick your brains for info?
After a long resistance, I finally bit the bullet and ordered a dedicated astro camera... the ZWO 2600MM-P.... which will be in my hands in around a month... But I have some reservations to whether I just spent a heap of cash for minimal or no improvement in my images.
Basically I have been using a full spectrum modded and peltier cooled Canon 40D, cooled using two peltiers on opposite sides of a cold finger, and the cooling works very well.... I have a temperature controller on the system with a thin temperature probe sitting between the cold finger and the sensor, this way reporting an accurate sensor temperature. I limit the cooling to 4 degrees C (it has reached -4.7C during a test, but the sensor hazed over)... I find that down to 4 degrees (with a heat strip wrapped around the front of the DSLR/Filter wheel connection) I do not have any condensation issues on most nights and at 8 degrees or lower, my ISO1600 subs are noise free, even if I'm exposing up to 1800 second subs.
Now to my dilemma, when I try to look up if anyone has compared a DSLR setup similar to mine to a dedicated astro cam such as the ZWO2600MM out on the field (as opposed to tech spec sheets), there aren't many comparisons and the two posts that I found that are the closest to comparisons show that there is not that much difference in the overall images... one camera was a cooled 40D compared to a QHY OSC camera and the images of the Rosette nebula (featured/tested/compared) were very similar and a image of M31 actually looked better taken with a modded Canon 5Dmk3 to the one imaged with a ZWO1600MM by the same imager, using the same scope!!!
Would anyone be able to answer whether I should be bracing for a disappointment?
Once I get it, I'll do a direct head to head comparison on the same object, same focal length, and compare both RGB and Narrowband imaging. (And I was having success in Hubble Palette style narrowband imaging with my DSLR so the statements, that are quite frequent or forums, that NB imaging with a DSLR is a waste of time are simply not true IMHO).
Thanks in advance.