CraigT82

Quite helpfully, Astrobin allows user input of the ambient temp at capture...

That's a beautiful image! Nice work

I was thinking about this... I think this would be the case if tracking were pixel perfect but your normal lunar capture is drifting and wobbling around the sensor and so the differences in pixel brightness below 850nm would average out over many pixels?

I'd recommended you use Autostakkert 3 for alignment and stacking, it's way way better than registax for this. Registax is still useful for wavelet sharpening though, and it's got a really useful RGB histogram balance tool that works well.

I've got a ZWO 850nm I can send to you if you want to test it. I used it pretty successfully on Venus with my 8.75" fullerscope at f/20. Obviously the smaller the scope it the dimmer the image but there is no solid cut off aperture so when you hear it recommended only for scopes over 10" that is claptrap! The 642nm bandpass outlined above? Also Baader 685nm longpass

Very nice Wouter 👍

That's a real stunner, very nice work!

Wouldn't touch that with a bargepole. If you can't get a reasonably sharp image of the moon through a telescope there is something very wrong. Way way more capable telescopes are available for 300 bucks

I used it for about 3 years before I realised you could do that!

Top right hand side there are several pink boxes, you input the number of frames or percentage of frames you want to stack in there and you can put in 5, 10, 15, 20 in the boxes (or whatever percentages you want) and AS3 will churn through in one go and create a stacked image for each percentage.

Not delivered by postie but collected myself, and after spending a bit of time at my workplace it's finally here at home. Battered old Skywatcher 300p newt! Requires 32kg of counterweight 😳 Looking forward to doing some hi-res lunar imaging, and planetary when that time comes.

Have just stumbled across this video of a talk given by Emil Kraaikamp to Telescopes.NET discussing planetary processing using Autostakkert, not sure if anyone has flagged this one yet? The video is 2 hours long but goes in depth to the different settings one can use for analysing and staking images and I learned a lot from it! Emil uses Autostakkert 4 which is apparently going to be released imminently and so you can also get a look at the new features.

Exactly what I did with my early 2000s eq6 after a full stripdown and rebuild. Also set the spur gear meshing whilst outside too by using the peephole. Always best to make adjustments in real working conditions and you can get immediate guiding feedback to see if it worked. One adjustment at a time though!

Perhaps this page is the one you looked at... http://slittlefair.staff.shef.ac.uk/teaching/phy217/lectures/telescopes/L10/index.html It has a very neat explanation to why smaller apertures 'cut through' seeing: Essentially the smaller the aperture the smaller the section of the distorted wavefront it samples, and the smaller the section sampled the more planar it appears to the instrument. Brilliant!

Is there any kind of existing data table of coherence times? Maybe with aperture down one side and seeing level across the top? Would be V.useful!

AS3 will handle small amounts of field rotation but for a significant amount the advance settings tab has a field rotation compensation tool. You do need to input some info though I can't remember exactly what, perhaps the rotation angle between first and last frames?

Are you sure it's a 2x barlow? Does it work OK with eyepieces?

Haven't seen those before, usual suspects in terms of sensors but one has a IMX464 chip which I don't think is offered by ZWO or QHY? Seem cheap initially but need to add VAT etc.

Have got it, picked it up last Friday but have been away from home this week and so not done anything with it yet. Will be adding a 120mm fan and baffle for the rear plus will wrap the tube with reflectix to reduce tube currents. Also got a moonlite base plate on order so I can fit my motorised CR2.

Absolutely fantastic detail there Roy. There's a bit of noise when you look into that expanded image of Ptolemaeus, have you tried stacking more frames to smooth that out a bit?

Neil this is astonishing! Looking at the 100% image that little scope is resolving details it has no right to. Absolutely everything must have come together for this one. Did you use any filter with the 462c? (Have just ordered a 462c myself) The overall tonality is just right for me, the contrast range is very natural and subtle looking.

Yeah I do see what you see too, the bottom image has more sharpness, but my point is that the difference isn't much (and may well just be down to a touch extra on the wavelets slider?), if you look at the smallest craters visible (which are a very handy indicator of resolving power) then the same tiny pits are visible in both images, which indicates to me that seeing was good during capture and if an ADC was used with the IR cut, or even just a shorter wavelength filter (G?) then the IR pass image would have been knocked into second place. To illustrate here is one comparison on Copernicus I did in good seeing, green filter Vs IR685. Here the benefit of the IR pass is not needed (due to the good seeing), and the shorter wavelength green has allowed resolution of finer detail. I do see a lot of people defaulting to IR pass filters for all their lunar images but my humble opinion is that the IR pass should only be used if the seeing won't tolerate any of the shorter wavelength filters (i.e. it is a last resort).

I'm not sure which ridges you mean?

Yes the bottom one is IR pass, it looks slightly sharper but in terms of detail there is nothing visible in that one that isn't just as visible in the IR cut image, and the sharpness boost may just be down slightly different processing (OP notes 'similar' processing). As the IR cut image contains all visible wavelengths from blue to red atmospheric dispersion will have an effect, the amount of which is dependent on the altitude of the moon at capture.

There isn't much in it to be honest, seeing must have been good. Here is a zoomed in comparison (IR cut top, IR pass bottom). Not sure what altitude the moon was for these, but the IR cut filter capture may have benefited significantly from the use of an ADC. Very nice images BTW!