Deadlake

In the EU fabricated by Haarder, ITAR prohibits the export of NVD’s from the US.

It has always been like this going back some years.... It might simply be due to hunters in the US using NVD's and hence there is a bigger market... Also the best tubes for astronomy have low EBI's, not really used for other applications as far as I know.

In Europe the price has gone up, however the cost of a good L3 MVD in the US is half the price including taking taxes into account. I guess the question is why the NVD kit is twice that in EU compared to US? Also all relative, the cost for a 20" dob set of mirrors in the EU is around EUR 10,000 excluding the frame, focuser etc. A 10" BS Newt + an EU NVD is less and you will see more and can use the NVD in more scopes.

I just need some good seeing to try out the HR 1.6 mm, no TOE to compare with there. 😃

The main reason for the HR range being discontinued is Vixen was not happy with the QA they could do on the EP’s. Having said that APM have ordered a new run of Doctor EP’s, maybe Marcus could be convinced he could do the same for the HR line?

Maybe back scatter, it’s there will every scope I’ve used the TOE EP with.

If this is a blueish warmth to the presentation then yes, not present on the HR.

I’m think the main difference in use is the TOE add a brightness to the object, however this really only pops up on the moon and a moon filter can control this. With average seeing the 3.4 mm HR and 4 mm TOE are the most used EP.

I like my small scope too for the wide fields of view. Very versatile as I can move it around the garden for tree dodging duties. Works best with XWA 20 mm or 30 mm UFF. Also very good for looking at the moon a x500. A great swap...

Yep, helps with high Strehl scopes around 0.98 to 0.99 to pile on the magnification. I have used a BRAVDA and 10 mm UFF on other nights, but comparison of performance is as ever seeing limited… If I had done my research based on CN feedback a high quality Barlow mounted ahead of the diagonal and a good 10 mm EP might give more contrastly views then some high end EP’s.

I prefer the TOE 4 mm. Having said that the seeing was so good tonight I spent most of the time using the HR 2 mm that the 4 mm didn't get a chance. 4 mm is usually most used when seeing is average on planets.

In the UK really need the planets high up, last few years low down and large depth of atmosphere to peer thru..

I had the fortune to have a TOE 3.3 mm and HR 3.4 mm using with an LZOS 130 mm on a night of exceptional seeing when viewing the Moon. Not much chance of looking at anything else this year due to the cloud cover. 😀 The one data point that the HR really showed it pulling away from the TOE was the level of shadow contrast visible within craters. At one point I had to pinch myself at the detail. Also the dynamic range as well, noticeable more than the Vixen SD103S scope I used to have which I feel was still very good. I also used a 2 and 2.4 mm HR, the scope just opened up with the level of detail on the moon, the limiting factor being I needed a guided mount to minimise vibrations. Note: using a Baader moon filter took off the extra brightness the TOE adds. Hoping for another good night, I'll try a BRAVDA and 10 mm UFF and see where that gets me.

I has to experiment with different EP’s and diagonals. However on nights of good seeing all is possible. Sometime best to have multiple scopes out to experiment with Barlow or BV’s side by side…

For planetary observations some of the best planetary views I had are by attaching a Barlow on the scope ahead of the diagonal (now running at F20) and using a 10 mm UFF EP or some BV's. This helps with bring up contrast from observation and also brings out the reds on Jupiter.

It was not just me, one of the best nights for seeing for some time. Why or why on a moon light night.....

4-9 Working days, https://www.bresseruk.com/Astronomy/Telescopes/Vixen-SD103S-apochromatic-Refractor.html Actually quite shocked how much SD80 as gone up, when I bought my SD103S the SD80 was around £900, not just under £1300. Well done government, this is not just global inflation.

I think the reason for little data is the hit on resale value, a theory but a reasonable one. With regards to red line testing, I think the current theory is that the blue line will be more optimised than testing in the green and the green line will also not be as high. Obviously eyes and CCD are more sensitive to the green line wavelength. At the same time if SV are forced to optimise in the green and red line then the produced lens will be made similar to how AP and LZOS produce their respective lens by testing with multiple wavelengths with an interferometer. Which is good for the quality on the lens, however will make them more expensive to produce.

At the moment there really is not enough data on SV's line up to call this one way or the other. Actually the only data points I see on this are for SV's with LZOS lens cells that are tested on the green line 😀. See: https://www.cloudynights.com/topic/868125-dpac-testing-repository-of-tests-performed-on-refractors/ Even what SV are going to do is not firmed up, originally they where going to move to testing in the green line and then that statement was removed from SV's site. Note: I've had to have Nic remove around 2 pages of comments around SV on a thread I have on CN as went off on SV tangent.

Gerry, Does the mount need tracking or not? If so I'd also look at the HAZ31. The weight is around 3.5 kg vs the AZ100 of around 10 kg. Note: I'm planning on getting the motor upgrade for the AZ100 I have, I would just like a more portable and compact mount for dark sites visits etc or tree dodging in the back garden. The HAZ31 is also a top loader which makes set up and tear down easier. The only caution is earlier shipments appear to have issues with the mother boards. If you get a working version the tracking is meant to be superb. The other gotcha here is balancing the scope. My tail heavy 105 mm LZOS needs a 1 kg counter weight on the lens end to balance when on the AZ100. The harmonic drive in the HAZ31 makes the need for a counterweigh redundant, you can change EP's from a 30 mm UWA to a HR 1.6 mm without a rebalance. I'm waiting on more reports but from the feedback I've seen very positive. M

I think Sixela has work arounds with this for this (in the thread on CN) so the bottom of the Barlow is flush and will not hit the diagonal. However how much back focus is required, that’s an interesting question.

It attaches to the bottom of the APM zoom, sold as a pack. Needs push fit adapter for the 1.25" barrel.push fit adapter

Gerry you might want to checkout the revised TMB APM Barlow, meant to give sharper stars at the edge then the VIP you are using, also very good used with Bino’s as well.

Did you mange to use the HR or TMB EP's at all?

You still got your Doctor? 😀