matt_baker

Thanks for this, for a sec I thought I was having some kind of issue. I'll try 480s subs but doesn't amp glow almost become a problem at that point, possibly even with darks?

Just had my first light with my 1600MM.

Looked at the suggested ADU values for lights and they're around 850 ADU at gain 139 offset 21

I live in a Bortle 5 area, so you would expect I'd be able to reach the desired ADU rather easily in 240s with my Ha filter.

I tried on two targets. The Eastern Veil and the NA Nebula. Maybe I should've tried a different, brighter target but my median ADU on a 240s sub was 400 and a 600s sub was 540

Am I doing something wrong or do I live in a darker sky than I think and can exposure much longer?

My Ha filter is the ZWO 7nm

Matt

Actually just bought one of those, should be arriving soon. 

1 hour ago, alacant said:

A DSLR requires 45mm. You have 6.

I thought you were using an así 1600.

Are you now using a DSLR? The clik lock will not work with a DSLR.

Cheers.

I'm using the 1600 yes and it does have 6.5mm backfocus but I have the MPCC too so after the FW and spacers are attached, that becomes 55mm

11 minutes ago, alacant said:

Focus is at the same point with or without. You have only about 6mm of back focus.

I keep finding replies like this saying otherwise about the clicklock

5 minutes ago, alacant said:

Hi

How about this?

But with close on a kilo of stuff that far from the tube on a budget focuser, well...

Just my €0,02.

Cheers

Do click locks not make the focus too far out?

Just got my 1600MM Pro and I'm wondering how to reduce the tilt with 130PDS and MPCC attached?

I have got 3 thumbscrews attached but I have a feeling they won't do the job so is there anything more I can do to reduce the tilt caused by the focuser without upgrading it?

Refractors are like the plug and play of telescopes. You won't have to deal with collimation etc. that comes with the learning curve of it, but they're more expensive per mm of aperture and some people prefer the challenge

IMO I would go for an Evostar 80ED or if you can fork out the cash, go with an Esprit 80 and you'll never need to buy another scope for widefield. Pair that with a HEQ5 and you'll be set.

For a camera maybe starting off with a modified DSLR is the way to go or if you're prepared to buy something like a 1600MM or a 183MM, go for those but they're pricey

It really depends on how much you're willing to spend since this hobby can get very expensive when you dive deeper. A part of me also says get the scope and a solid mount, and master with a DSLR, then if you want to dive further, go for a cooled CMOS/CCD

2 hours ago, richard ashbee said:

worth all the effort

It really was

Just trying to wonder how to reduce the tilt with a DSLR as I think your way would increase the spacing and I wouldn't want that

4 hours ago, Adam J said:

Yes it's the case for anything with a half decent aperture so 80mm refractors and over. You will want at least a HEQ5PRO. I used a 130pds on mine and I am sure a lesser mount would have been a massive pain in the bottom. The HEQ5PRO is the cheapest mount on the market that will provide consistent sub ascsecond guiding on such scopes. 

Adam 

How do you deal with focuser sag with your FW + 1600MM? 

3 hours ago, jgs001 said:

Fantastic, and that sounds like a huge amount of work.

Yes, it really was and took about 3 hours to stack all the files then I had to stitch the final result together

4 hours ago, bottletopburly said:

Impressive Matt 👍

Thanks!

Moon wasn't the highest last night but I tried doing this monster mosaic which took about 2 hours to complete.

I took 500 frames per panel to save storage. Ended up being about 55GB of memory in total for all 90.

Made sure there was plenty of overlap so could have ended up with less panels overall but got to be sure when you're doing something as huge as this.

Imaging telescope: Celestron C14

Imaging camera: QHYCCD 5L ll M

Mount: Celestron CGE

Software: Photoshop, Autostakkert! 3, PixInsight 1.8

How worth it would it be to get a moonlite focuser for the 130PDS vs buying a used 80mm triplet?

1 hour ago, Stuart1971 said:

There is a filter, you can show whichever ads you want to see, for sale or wanted, or all... 👍

Ohh actually only just realised after all this time you can do that aha

6 minutes ago, Solar B said:

Is it me or has anyone noticed the amount of "wanted" ads on UKABS 

There's almost as much wanted now as there are for sale and I've noticed this grow 

over the last 6 months , I'm guilty of some wanted ads myself but the thing is hardly 

worth looking at any more me thinks 🤖

Brian 

I think there should be a filter for wanted ads

Here's a 10 minute sub of the Elephant's trunk. The left side stars look pretty similar to me.

Was taken with a 2 inch Duo band filter on the end of the CC instead of clip in

How would I go about adding or removing space?

I'm not sure what kind of issues are occuring here with the shape of my stars.

I've already drilled and tapped a third thumbscrew to reduce sag and loosened the mirror clips enough to slide a credit card underneath.

I use a 600D and a Baader MKIII CC with a Celestron EOS T ring. I've seen above and could it be down to the spacing being off on the MKIII?

The only thing is that the stars on the left side of the image I've attached are a different shape to the right side which makes me wonder what's causing both.

Any help would be appreciated 

This sub was 120s with a CLS-CCD clip in filter, guided in PHD

Matt

I'm stuck on deciding between upgrading my 130PDS to an 80mm triplet or saving a bit more to buy a Mono CMOS which would theoretically cost me £230 less for the camera if I sell my 600D and about £180 savings if I sell my 130PDS

2 hours ago, Dan13 said:

I got the SW one (non x.09 reducer one) litterly plug and play. Rother valley have it , FLO doesnt 

How far in is the focus?

I've now taken all the frames and divided them by 2 to get the mean and safe to say, there is a spiral

Can be seen here:

I've blinked the calibrated and registered frames and the stars are completely fine, no rotation whatsoever, although it was slightly rotated from a separate night of imaging.

Surely that would have been dealt with when they got registered. 

I guess I'm just not dithering enough. I have got a beefy ST102 as a guidescope and it's only 150mm out of my 130PDS at 500mm, and the scale must be messing with the settings, which makes it not move enough?

Here's the rejection high and you can clearly see the spiral

I've ended up trying a plethora of different rejection algorithms and sigma values, none of which have fixed the issue. I also put my bias as bias. I did notice something odd however.

The noise seems to be like it's orbiting a central point, like star trails.

Here's an overstretched example:

Note how the streaks aren't in a constant direction like typical walking noise

I have a bit of a strange issue.

I've given up using darks with a DSLR since the temperature varies by 3-4 degrees throughout the night, so there's no use in darks. Instead I've just been dithering by the max setting of 5 in APT and using my superbias as a replacement for my dark.

In WBPP in pixinsight, if I check the calibrate dark frames, it skews my flat and makes the image look awful but there's no walking noise. However if I uncheck it, my flat frame gets calibrated just fine but it introduces walking noise to the image.

Is there something I'm doing wrong?

Here's an example of the noise stretched out

Okay, so I've added 3 hours more data but now I'm getting what looks like walking noise in the image and I don't understand why. I'm dithering on the max setting in APT which is 5 with PHD 2 guiding. I did notice when it did dither that my graph didn't actually seem to move when the dither command was sent on some of the frames. Maybe some of them didn't actually dither properly when it was supposed to?