Tim

9 hours ago, JamesF said:

"Darling, I need to buy some more astro gear"

"Oh really.  What is it this time?"

"A chainsaw"

 

LOL! How true in so many cases!

8 hours ago, carastro said:

 I am afraid I am a bit of a dinosaur and do most of my stuff manually, and only walk away when it's all up and running OK.

Me too!!  Are you at Kelling this year Carole? Be nice to catch up, I saw your camper last year I think but didnt see you

2 hours ago, Icesheet said:

I know there is the argument that you should focus between each filter but I’ve also read that it’s only really critical for your Lum to be in focus for the detail.

Not sure if anyone has thrown this particular spanner in the works yet, but there are very few refractors that have such perfect colour correction that there is not a bit of star bloating from not quite precisely focused colours being captured during a Luminance sequence. Faster 'fracs are the worst offenders normally, and it isn't always a case of the more expensive, the better. Take Vixen's VSD100 as an example, Luminance subs through that lens were pretty much impossible to get tight focus on when I used one, and as was stated in the offical S@N review too.

22 hours ago, pete_l said:

The point about OSC is that you get something, quickly. And after that each additional sub adds to the overall quality of the image. You can therefore stop when you are satisfied with the result. Or when conditions dictate. And when you stop, you have usable data - you aren't missing a channel or with an unbalanced exposure on one part of your palette.
As for chasing the very faintest whiffs of nebulosity? I think we all understand that most OSC users (myself included) are not after those sorts of results. There is plenty of stuff available for DSLR / OSC imagers to capture without needing to go deeper, darker or to large + expensive imaging rigs.

It is, after all, a hobby.

^^^  This ^^^

What telescope were you looking to use it with btw?

Nebulae imaging?  Mono camera with narrowband filters - no brainer

I have both ways and each have their uses, there is very little crossover to be honest.

If you are lucky enough to image with a scope without CA, then OSC can be useful for our rubbishy UK skies.

If I was to just choose one, then it would be a mono, for most versatility. But OSC certainly have their place.

Just my $0.02

Tim

15 hours ago, geordie85 said:

...................IAS this year, especially as FLO will be attending. 

That's good news. I just drove past the pub we went out to last time FLO did a local (to me) show and was thinking about it. Ted came from Borg too.

21mm Ethos.

No, 13mm Ethos.

No, 10mm Delos.

No no no, 21mm Ethos definitely.

I think....

erm....... hmm, not sure.....

On 02/08/2019 at 14:50, Mr Spock said:

I'd like it, but, I'll need to check my lotto numbers first... 

We'd all like it Michael   Might struggle to pass this as "allowable expenses" though

Have you looked at the ASiair?

If the ASI1600 is compatible, and I havent checked, you can run both cameras from that, plate solve, link to Skysafari, and generally do away with a laptop......

This is excellent news! Can't tell you how pleased I am to hear this, for both parties. Congratulations FLO and Ian.

Tim

How about bigger?  The new WO 126 looks promising, 970mm focal length

On 28/03/2019 at 01:39, symmetal said:

Here's the results from last night white RedCat tests. They are 15 sec L exposures on an ASI1600

1

Following this thread with interest

At least from the White Redcat you have equal effects of coma, and it is not too awful. It's a shame there isn't a way to get software adjustment suitable for each telescope and camera, the same way you can get software adjustments for Canon lenses for example.

Out of interest, is the coma worse if you focus and image via a blue filter? Use a central bright star to focus and then nudge the same star to the edge of the field and try again. This will also demonstrate the extent of any focal shift. If you have parfocal filters it will demonstrate how "apo" the scope is too. Luminance filters are a compromise in refractors, there is nearly always a bit of deviation in one of the colours, usually blue, even with fluorite lenses. 

Cheers

Tim

This is brilliant, great colours and processing, you must have enjoyed some lovely dark skies for this

Having used most variants of scopes for imaging, I would suggest an RC is perhaps not an ideal starter scope. There are so many other things to get right, you dont want to be mucking about with the scope too. Hard to beat a decent refractor for starting out with AP.

RC telescopes are generally  better for photography than for visual use, the large central obstructions reduce the contrast at the eyepiece.

Colliiating them can be the devil's own work, but once properly set, they can produce excellent images. There is a review of the Omegon RC telescope in a recent Sky at Night magazine.

On 26/09/2018 at 15:31, Stu said:

Haven't seen it, but I'm sure it will be up to your normal standards Tim, thanks

Thanks Stu.  I have just read the review to see how much resemblance it bears to what I wrote

The editors, bless them, missed off a crucial detail. The part about the star test, should read:

Quote

Our green filter and 4.5mm lens gave a round star with concentric diffraction rings, 1mm of defocus either way giving a sharper pattern inside focus.

Italics reveal removed text. Without it the sentence is meaningless. You'll have to buy the magazine for the full review  Or do a "John" in WH Smiths.....what a nerve

Latest S@N magazine has a review in, including details of how the scope performs photographically.  I'm still on holiday at Kelling so haven't got my copy yet at home, but I noticed it on the newsagent shelf yesterday.

Good  move FLO

I wonder though, how many observers would have been more than happy with the first scope John received?

I have attended many star parties where people are joyfully observing through equipment that has been poorly collimated, with sub-standard views, but they are more than happy with what they see. I usually pass on commenting about the collimation, unless i'm asked.

I still wince over an episode at Kelling SP once though, when Es Reid was examining an 18" mirror I had from OOUK that had terrible astigmatism. I always collimate my newts with the Cats Eye tools, they are expensive, but worth it for the last word in collimation. After we had been dodging around the sky a bit, star testing, Es just mentioned, in passing, "your collimation is a bit off...."     Aaaaarrrgh! My eye is twitching even thinking about it! 

Is there an ETA on the new scooe for John??

7 hours ago, DRT said:

I'm Scottish and have never seen nor tasted a deep fried Mars bar in my life.

Me too, me neither!

I fear for this thread now, the scope is on hold, the weather has turned cloudy, and the mob grows restless.... but if you cant beat 'em....

7 minutes ago, paulastro said:

Don't know about the people you mention, but in some parts of Wales I believe they speak Welsh all the time,

Even when they are asleep?

Half of my wife is Welsh,  but it is ok because the other half is Scottish. Imagine Catherine Zeta Jones making deep fried mars bars and you pretty much get the idea

4 hours ago, gorann said:

 why is the glass composition a secret?

Perhaps  not so much a secret as  much as irrelevant to most purchasers? I also have no idea what type of glass is used in my Televue eyepieces, but I know that they work well

8 hours ago, wimvb said:

In the mean time, an Es Reid test can provide the quality control that should be SOP in China. The scope just became £ 75 (which I believe is the price FLO  usually adds for a test) more expensive than its list price.

The list price for the 150ED is £1699 on OVL's website IIRC. So actually, a buyer would still be 4 quid better off

58 minutes ago, FLO said:

We will endeavour to put a good example in John’s hands......

Steve

Musing > It would be nice one day to have a reputable top UK supplier with an optical bench and staff trained by a certain Mr Reid, perhaps before said Mr Reid hangs up his gloves for good.

My fear is that a lot of the skills our hobby depend on are at risk of dying out with nobody rising to take up the mantle... mirror makers, optical gurus, mirror aluminisers, lens polishers.......

I do hope SW can iron out the wrinkles with the first batch of 150EDs, they have always been pretty good at improving QC when necessary.  

On 03/08/2018 at 20:35, dweller25 said:

Daniel Mounsey - an American astronomer (and US vendor) has compared the SW 150ED to a TEC 140 triplet and found very little visual difference.

https://www.focusastro.org/equipment-reviews

I expect the SW150ED would outsell TEC140's by a considerable margin?

Thankfully, the review here was not conducted by James, Steve, or Grant from FLO, and carries all the more authority for it. ?