johnturley

I actually have a Nadira folding chair now which I purchased from Rother Valley Optics, its not ideal but it does fold up small. I also have some steps on wheels, on which I place my laptop when doing astro-photography, I just couldn't wheel them around the shed with the original bulky observing chair in place. John

It was made by a carpenter friend some years ago, based on a design in a old Patrick Moore book, but I don't use it now as its rather bulky. John

This is possibly one of the best photos taken at the time I had an Astro Physics (early pre-Starfire) 6in f8 Refractor piggybacked. I now have an Esprit 150 piggybacked, it might surprise some, but the Esprit 150 is much better colour -corrected, and gives sharper images. John

Binning didn't give good results on planets when I've tried it. John

It's a bit like saying that a magnification of 50-100x with a 6-12in telescope on Jupiter will reveal all the detail that it present, but most people consider it more aesthetically pleasing when viewing conditions permit, to view it with a magnification of 200 - 300x. John

Looks like, due to Jupiter's varying inclination (only 3 degrees though), Ganymede is only just touching the Jovian disc, I assume Callisto will be missing it completely. John

Sounds impressive, and at a very competitive price too at around half the price of the Esprit 150 (and lighter too), and less than 20% of the price of a premium 6in Refractor such as the Tak TOA 150, or TEC 160. I think that it is very similar (if not identical) to the TS 150 John

I am planning to get a Takahashi 100 DZ Refractor after selling my Celestron CPC 9.25 (selling due to back problems), and although I usually buy most of my Astro stuff from FLO, I will probably get the 100 DZ from Rother Valley Optics (who are just 15 miles away from me), so that I can pick it up in person, so as to avoid the risk of any possible damage or misalignment of the optics, due to rough handling by the courier. When I purchased my Esprit 150 (from FLO), this was 'drop-shipped' direct from OVL (the UK Skywatcher distributor) to ES Reid for testing, and I arranged to pick up the scope direct from ES (whom I know personally) after testing. I will however, probably buy the tube clamps and saddle plate to attach the 100 DZ onto my AZ-EQ5 from FLO, as they offer a better choice which are more competitively priced. FLO also appeared more knowledgeable than RVO in so much as they pointed me towards an adapter bar to enable the attachment of the Takahashi cradle to the AZ-EQ5 mount, whereas RVO said that it wasn't possible. Utilizing this adapter bar with the Takahashi Cradle, however works out more expensive than the StellaLyra 95mm tube clamps, and I gather is also less stable. John

Just received notifications from Harrison Telescopes, that they have now shipped the 42mm Vixen LVW. Although their website showed that this eyepiece was available, I did have my doubts as to whether they would be able to supply one, as Vixen ceased production some time ago, none of my 'usual' retailers were listing it, and it does state on their website that this product comes direct from their supplier. In fact its still showing up as available in case anyone else had thoughts about getting one. John

As some have mentioned previously, it is not possible to get a 52 degree field with a 1.25in 40mm eyepiece, unfortunately some manufacturers do overstate the apparent field of view of their eyepieces, or quote the average for the range, and the longer focal lengths have smaller APFOV's. John

Astronomy Now, as it is based on a UK perspective, and only lists for example phenomena of Jupiter's satellites that are visible from the UK. John

I don't find the Aspheric 36 too bad in my f7 Esprit 150, but the edge quality is rather poor in my f5 Newtonian, hopefully (assuming that it arrives) the Vixen 42mm LVW will be better in both, besides giving a slightly wider field of view. John

Thanks for the info. I have now successfully placed an order with Harrison Telescopes, so remains to be seen whether they will actually be able to supply one. Assuming it does arrive, I will compare it with my 36mm Aspheric, and 56mm Meade Plossl, and if it compares favourably, possibly sell both of these. My Meade 56mm Plossl is actually one of the original 5 element made in Japan eyepieces, so may fetch a bit of a premium price. John

According to Harrison Telescope's website they still list the Vixen 42mm LVW with availability in 5-7 days, and tried doing a dummy purchase and it went into my basket, but not sure whether they still have one in stock. Even if they still have one available, I'm a bit undecided as not sure whether it would be a significant improvement over my 36mm Aspheric. John

Mr Spock Do you have a 42mm Vixen LVW, I was wondering what the edge performance would be like in my f7 Esprit, I assume that it would be superior to my Baader 36mm Aspheric. I already have a StellaLyra 30mm UFF, which I use as my lowest power through my 14in Newtonian, hence was thinking of using in my Esprit (which is piggybacked on the Newtonian) at the same time, and selling my 36mm Aspheric, and possibly also my 56mm Plossl. Not many suppliers currently list the 42mm LVW, so wondered whether it had been discontinued, in which case if I want one, I need to order it fairly soon. John

Although the 30mm UFF is no lightweight at around 550g, it is considerably lighter that a lot of other equivalents, such as the 24mm ES 82 at around 800g, or the 31mm Nagler or the 30mm ES 82 at around 1.2kg. John

The 30mm StellaLyra UFF, although no lightweight at around 550g is considerably lighter than the ES 24mm (around 800g), and I much prefer it to the latter through my 14 in f5 Newtonian. I also prefer it to my 36mm Baader Aspheric, stars being much sharper near the edge of the field. The 36mm Aspheric is not too bad though through my f7 Esprit.

I used to find Enceladus fairly easily with a 10in Newtonian in the 1970’s, but now struggle with a 14in Newtonian. I put this down to combination of increasing light pollution, and my deteriorating eyesight. In addition Saturn was higher in the sky for most of the 1970’s. Likewise I have never been able to spot Neptune’s Triton visually, although some people (no doubt with darker skies, and better eyesight) state that they have been able to spot it through a 6in telescope. John

What size scope was that with, the other night I found Rhea fairly easy with my 150mm Refractor, but could could only spot Dione through my 14in Newtonian. As mentioned earlier, in the 1970's I found Rhea, Tethys, and Dione, and occasionally Enceladus, fairly easy through my then 10in Newtonian, but then Saturn was higher up, my eyesight better, and skies less light polluted.

I've never been able to see Triton, or any of the moons of Uranus visually, even through my 14in Reflector going back to the 1980's, when my eyesight was better than it is now, and when I found the fainter moons of Saturn much easier spot than I do now. It will depend to a certain extent on how light polluted your location is. John

If you try to photograph the Moon and the Pleiades in the same frame, I think that you will find the light from the moon will swamp out the Pleiades most of the time, the exception would be when there is a thin crescent moon close to the Pleiades in the evening in the spring, or around July in the morning sky. John

You state that the chip size is irrelevant, but the general consensus on this site appears to be that for planetary imaging you need a camera with a small sized sensor, and that digital SLR’s are not ideal for planetary imaging due to their relatively large sensor size. If this were not the case, then why would some observers have 2 or more cameras one with a small sensor for planets, and one with a larger sensor for deep sky objects, if the camera with the larger sensor would suffice just as well for both. Having said that, I accept that for a given optical arrangement, the size of the image on the sensor will be exactly the same regardless of the size of the sensor, or the degree of cropping used. It appears to be that the software used for image viewing just displays the images taken with a small sensor and/or cropped as being larger, which makes them more aesthetically pleasing, and easier to process. I would love to see a large detailed planetary image taken with a digital SLR, using no more than a 2-3x Barlow for amplification, which you and some others say is possible. Some observers are also of the opinion that around 2x oversampling gives better results than the theoretical optimum of around 3x the pixel size. I suppose it’s a bit similar to saying that with for example a 6-12in aperture telescope a magnification of about 50-100x is capable of revealing all the planetary detail that is there, but most observers find under good conditions, using a magnification of 200-300x more aesthetically pleasing. I will however try doing some imaging closer to what should be the optimal focal ratio, using additional cropping or the drizzle function in Autostakkert to increase the image size to see whether it does give better results John

Last night had my best view of Saturn this apparition, and look my first image, taken through my Esprit 150 using a 2.5x Powermate, and processed in AutoStakkert and Registax, and a bit of polishing in Lightroom. P.S. I have processed another Sharpcap video since this morning, and attach the latest one, which I think is somewhat better than the original. John

Nicolàs You make no mention of sensor size or capture area, I don’t know by how much, if at all, you can crop the capture area with the Canon 1200D, but it will be almost certainly less than with a dedicated planetary camera. So if Pankaj uses his 10" f/5 Newton with 2x Barlow and his Canon 1200D (Aps-C sized sensor 24x18mm), using no more than a 2-3x Barlow for amplification, then I think that he will be disappointed with the resultant small image size. My first attempts at imaging with my ZWO ASI 462 Planetary Camera (which has a sensor size of just 5.6 x 3.1mm) through my Esprit 150 weren’t that great, as I didn’t appreciate that you need to crop the capture area to get an image that appears to be of decent size. My first attached image taken in August 2021, shows the result of an uncropped image at the native f7, which isn’t actually far from what is supposed to be the optimum of 3x the pixel size of 2,9 um. Although the size of this image can be increased using post processing software, I found that if I tried to do this by more than 2x, the results weren’t great. The second attached image was taken with the same setup, taken in October 2022, but using a 2.5x Powermate, giving f17.5 (nearly double what is supposed to be the optimum), and cropping the capture area, giving a much larger apparent image of reasonable size. I think that you will agree that the second image, which shows the GRS, is much better showing far more detail. The third attached image taken in August 2020 shows what I achieved using eyepiece projection (I think that I used a 12.5mm Plossl) with a Canon 6D full frame digital SLR, if I had just used a 2-3x Barlow, the image size would have been much smaller. At the time Jupiter was quite low down, and it was more difficult to focus through the camera viewfinder. John

Nicolas But you are using a C11 Edge HD (focal length 2,800mm), I think the situation would be somewhat different for someone using a much shorter focal length instrument, say 500 - 1,000mm, or a much larger sixed sensor than your ASI 174, or ASI290, as with a digital SLR. John