john2y

Hey guys,

I have an Explore Scientific 102/714 APO and I use it with ASI1600MM and it works great, recenly I've been thinking about upgrading my reducer/flattener to some that can correct wider field so I could use my Canon 6D with it. I found couple of 0.8x reducers that would fit my needs but they're for 2.5'' focusers and larger. I wouldn't mind getting a new focuser too (mine is 2''), the problem is that I've read that ES doesn't have officially switchable focuser and I'm afraid that if I'd get a new one, it wouldn't fit. 

So my question is, do you know about any focal reducers around 0.8x that are for 2'' focusers or does anybody here have an experience with swapping the focuser on an Explore Scientific refractor?

Cheers 

Jan

I'm an idiot, exactly as Jkulin says. I almost never do a calibration and once I did it it fixed the problem. 

Thank you everybody for the help and suggestions. 

Hey guys,

so we've had a lot of cloudy nights lately so I had a ''briliant'' idea to update all my drivers and firmware. That included my CEM60, I got the latest firmware for DEC, RA and MAIN board (also HC but I don't use it or even connec it to the mount) and the iOptron commander with the ASCOM driver. I got the latest non beta version of PHD2 and bunch of other stuff. The problem is that tonight when I started the sequence in SGP everything went well untill PHD started guiding, once it did a correction on DEC, my mount just started slowly drifting in the opposite direction of that pulse and PHD just wasn't capable of correcting it. After couple of attemts and bunch of resets I didn't get anywhere. It does it only in DEC, RA is guiding normally and it does it both ways depending on the first pulse it receives. Any ideas on how to fix it?

Cheers

Jan

It looks like a really nice image but I'd definitely crop out the stacked edges, also try to denoise it a little less, a little noise is better than completely smoothed out image 😉 

So about two months ago I did a widefield of the Cepheus using my Canon 6D and Samyang 135mm. Out of curiosity I cropped the Shark out of the image, using dynamic align I align it with my luminance data, then I really strongly denoised it and combined it to make LRGB image and even though it looks bad as an image it looks good as a preview of what I'm gonna get when I'll be done with it 🙂 

You got good data but something wrong has happend during processing, using deconvolution you've managed to produce some artifacts that look like a white thread and the stars are really deformed possibly due to excessive use of star reduction.  Try some reprocessing it I believe you'll get much better result 😉 

New update in the first post 🙂 

It looks like really nice image but try to reduce the chrominance noise either in Pixi using MLT or photoshop using Luminance denoise and cranking up the color noise reduction. 

Thank you for the compliment but it wouldn't be possible without such good data 😉  about the noise, try cutting the exposures a little, it might be that but I don't think so, I use asi1600mm and I do 8min exposures but as I've said the data looks solid so you'll just need some experimenting, you could also add more data, that always helps if you're not running 40 hours already 😄 . About the processing it just takes practise, I usually try to process at least one image per day, even the same one over and over. Practise makes it best 🙂 

This is what I've come up with, I've never seen data so clean, so well applied flat and everything and yet I had trouble denoising it which quite suprises me and I don't know the cause of that. I started by resampling it by 50% then manual DBE, TGVDenoise, LRGB combination as HOO, Masked stretch, Lum mask and playing with curves, Range mask and another curves and then ACDNR for smothing the background. 

What filters are you using, they seem really good. I'm asking as I use ZWO and they're not the best. 

This is an awesome image but I can't help but notice the vertical banding. If you're using Pixinsight for processing, try Canon Banding Reduction script, it should get rid of all the bands 😉 otherwise it's an excellent result 🙂 

On 28/08/2019 at 14:46, emyliano2000 said:

It's no problem. The black in the center was probably caused by me not applying GradX in photoshop properly. Maybe I should've done a few iterations of DBE instead of only one ABE.

When I get home I could share the stacked fit file and you can have a play with that. With the jpeg it looks like you lost some of the nebulosity.

Emil

I'll gladly have a look at that 😉 

Sorry for tinkering with your data, I just wanna show what I ment, background does shine, it's not pitch black but it also doesn't shine like the nebula in front of it. If you look at your image, the background in the center is black but outside isn't. I did manually DBE (and yes there was a gradient from the center to the edges) and then just applied inverted luminance mask and using curves I slightly lowerd saturation and brightness of the background. It's jpeg so it's not ideal but you get the gist. 

First post was updated with a preview of the mosaic  

I know you were trying to pull as much nebulosity as possible but the background doesn't shine like that, what program do you use for processing? It also looks like your flat didn't apply correctly as the edges are much brighter than the center of the image. Overall the data looks really nice so it would be shame if you didn't give the processing another go  

5 hours ago, dave_galera said:

Nice image but yes I agree on the noise. I always use MureDenoise on the Ha, OIII and SII masters just before they are combined, however, there may be problems with MureDenoise and variable gain cameras. This article refers https://pixinsight.com/forum/index.php?topic=9206.0

Thank you for the tip! I'm looking into it and just from what I've tried in pixi just to see what's it about I really like it.

5 hours ago, alan potts said:

Wonder ful shaot there, I think it's very nice. When I see this It always reminds me of Yes with Rick Wakeman playing all those keyboards around him.

Thank you, I googled few images and I know exactly what you mean  

This image consists of 4 widefield panels taken with Samyang 135mm on Canon 6D this year in Chile while I was visiting for the eclipse. Under really dark skies it is a naked eye object. 

Hey guys,

few weeks ago I started shooting the Wizard nebula in narrowband so I could process it in SHO. I was originally planning on doing 10 hours per channel but then I've decided to cut the times short as I started a different project which is much bigger than this one (the Dark shark nebula)

I ended up with 6 hours of Ha and 2 hours of Oiii and Sii each. 

Processed it in Pixi and even though the image is noisy and the stars look terrible, it's done. Next time I'll try to do better.

Cheers 

Jan

That image looks great and I admire your dedication for this one, but something's wrong in your imaging train, look at the stars in your top right corner. It's like the camera was pulling on one side of the focuser so much the sensor stopped being parallel with the rest of the imaging train. I used to have the same problem, I'd recommend checking the stiffness of the focuser and retightening of every screw around it. Also this might be just my taste but I would hold back on with the denoising, with 53 hours you don't really need it and the result looks a bit too plastic. A little noise is good it adds sharpness to the image. 

It looks like something in the imaging train isn't parallel, otherwise the stars would look the same in all corners. Check the tightness of everything. Definitely use the L filter as it cuts UV/IR. 

Hey guys,

three days ago I started gathering some data for the Dark shark. Due to the FOV of my setup I can't fit the whole nebula in one pic so I'll have to do a 2 panel mosaic. As it's my most favorite nebula and so far I only captured it in a widefield using Samyang 135mm with Canon 6D so it was super tiny. Now I finally tunned out my setup to do it properly. As I already mentioned I think it's just so amazing and the resemblance to a shark is really uncanny so I'm planning on spending some real time on this one. I've planned out 15-20 hours of luminance data for each panel with 5 hours for each colour filter for each panel. My current record is 22 hours of integration time and I aim to surpass it more than twice 😅. It's gonna be real pain but I really hope it'll be worth it. 

This is the result so far after three days. 103x5min (8,6 hous) of L data for the left part of the mosaic. I was surprised how visible it is after this short amount of time, I processed it in Pixi but only did DBE, Stretch, Resampled it down by 50% and fiddled with curves. In the full resolution the noise is still problem but it should slowly disappear after I add more data. 

Telescope: Explore Scientific 102/714 APO Triplet with 0.8x reducer

Mount: iOptron CEM60

Camera: ASI1600MM Pro - Gain 0, Offset 50, Cooled to -20

Update 28.8.2019:

Last night I finished shooting of the head part and mannaged to squeeze a few shots of the tail part as well so this is first preview of how it's gonna look like  

You can see the difference between the head with 12 hours of data and the tail with just one and a half, I need some clear moonles nights. 

7.9.2019 Update: 

I've managed to finish Luminance acquisition, so far 31 hours but I had to throw 7 hours out due to a lower quality. Now I'll have a couple of weeks of NB imaging as the moon starts to grow, then I'll hopefully do the RGB.

Cheers 

Jan

That is beautiful, I'm saving up for secondhand 6D and images like these just make me want it even more ?

6 hours ago, happy-kat said:

Why not try the free trail of StarTools, it is a fully working version just can't save so do a screen grab while trailing it. The cost of StarTools will bring many great tools plus an excellent gradient remover and it is about the same cost of just gradient exterminator plugin for photoshop.

 

It looks like the gradient removal process clipped the background completely so it's just black. Also some nebulosity got clipped as well.