Did my Zoom out perform my Ethos????

[Mark at Beaufort]

Last night I used my 12" Dob to view PNs in Aquila. One of the objects was NGC 6852. This object was quite faint although the milky sky did not help. What surprised me was I could see the PN in my TeleVue 8-24mm Zoom but not in the 13mm Ethos.

So it useful to try different EPs when trying to observe faint DSOs

[Moonshane]

Interesting Mark. I presume you were at the 13mm setting on the zoom? If not perhaps increased contest at higher magnification helped?

[Dave In Vermont]

That must be an old 8 - 24mm Zoom then. TeleVue® stopped selling those many years back after they were found to be the same as the Vixen LV (Lanthanum) ones. But that would serve to explain how you got such excellent results! Those Zoom's are great! I have the same one - branded Vixen LV - as you used.

Hang onto that piece of glass, Mark. It's not only an excellent Zoom, it's a very collectable and scarce item!

Congratulations -

Dave

[John]

Interesting report Mark.

Magnification can make a difference as Shane says. Otherwise I guess that the zoom was just the right tool for that target under those conditions. It goes like that sometimes. Another night the Ethos will shine. Dangerous to jump to conclusions about an eyepiece until it becomes a consistent pattern I've found, having parted with a few over the years only to have to re-buy the darn things

On the TV zoom - Vixen made it for TV and they ran the model for 20+ years. They never made any secret of the source of manufacture contrary to the tales that Dave loves to tell

[Peter Drew]

Always worth trying different eyepieces on the "horses for courses" basis. For faint, smallish objects like PN's a simpler form of eyepiece containing less elements can provide improved light transmission. Comparing views directly does require similar magnifications a Shane mentioned.    

[Mark at Beaufort]

The zoom was set at 16mm so not quite the same as the 13mm Ethos. I had to use averted viewing in the TV Zoom but the PN was quite obvious.

I recall several years ago using a Hutech Ortho and being able to see fainter stars against my more expensive EPs. Its a pity but I could never really get on with Orthos. Perhaps I should give it another go.

[John]

3 hours ago, Mark at Beaufort said:

The zoom was set at 16mm so not quite the same as the 13mm Ethos. I had to use averted viewing in the TV Zoom but the PN was quite obvious.

I recall several years ago using a Hutech Ortho and being able to see fainter stars against my more expensive EPs. Its a pity but I could never really get on with Orthos. Perhaps I should give it another go.

Perhaps the narrower field of view was a factor Mark ? - less space to search for that small faint object ?

FWIW last night my Nagler 2-4 zoom was showing Triton more readily than the 4mm HD ortho that I also have. The latter is a clone of the Astro Hutech / Fujiyama orthos. The folks who use really big dobs in the USA deserts looking at really faint stuff prefer top flight orthos over other eyepiece types. The Baader Classic Ortho 10mm does well in those circumstances as well, apparently.

[Louis D]

I've found zooming in and out can help separate faint nebula from the background skyglow in much the same way that sweeping the area does.  The moment I stop changing the size/location of the object, it disappears.  This is a function of our brain's ability to pick out faint, changing details in our field of view.  It's similar to not being able to see an animal due to its effective camouflage until the moment it moves.

[John]

14 minutes ago, Louis D said:

I've found zooming in and out can help separate faint nebula from the background skyglow in much the same way that sweeping the area does.  The moment I stop changing the size/location of the object, it disappears.  This is a function of our brain's ability to pick out faint, changing details in our field of view.  It's similar to not being able to see an animal due to its effective camouflage until the moment it moves.

Rather similar to nudging the scope slightly - a good tip to help pick out a faint DSO in the field of view

[Piero]

45 minutes ago, Louis D said:

I've found zooming in and out can help separate faint nebula from the background skyglow in much the same way that sweeping the area does.  The moment I stop changing the size/location of the object, it disappears.  This is a function of our brain's ability to pick out faint, changing details in our field of view.  It's similar to not being able to see an animal due to its effective camouflage until the moment it moves.

I fully agree with this. 

I also think a 13mm UWA and a zoom are two very different eyepieces on an F5-6 telescope. I would opt for a zoom when looking for/at a PN, planets or small targets, but for a medium power overview of a large target or multiple targets (e.g. collection of galaxies), a large fov is very nice.

[spaceboy]

I noticed similar regarding wide fov eyepieces and this thread has made me think back to a tread I posted. This is going to sound totally stupid but with a wide fov your going to get more stars in the view so more stars more light ?? More light but maybe a smaller pupil dilation ?? Less fov, less stars, less light and a slightly larger pupil allowing fainter objects to be seen???

I noticed my BST starguiders were ever so slightly out performing my ES82° eyepieces regards showing slightly fainter stars. The contrast was ever so slightly improved also. We are talking eye straining improvements and I really had to concentrate hard to notice the differences but they were there.

 

[jetstream]

On 8/28/2017 at 04:52, Mark at Beaufort said:

The zoom was set at 16mm so not quite the same as the 13mm Ethos. I had to use averted viewing in the TV Zoom but the PN was quite obvious.

Perhaps the greater eye illumination at 16mm focal length played a role? I also find zooms ideal for PN and will use them to get the best mag for the object and then compare eyepieces of that focal length to it. Honestly most other eyepieces won't trounce the zooms on these but certain objects like certain combinations IMHO ie the fantastic Eskimo nebula/Docter/VIP combo.

The 3-6 Nagler zoom is not my first or second choice for planetaries I must add...

Great to hear you had some nice observing Mark