Rifle scopes with no focus or parallax adjustment knob
-
Help me understand how a scope with no focus or parallax adjustment stays focused over its entire magnification range, at all distances. While I was dealing with my Vortex razor hd issues, I installed a 4-12x40 Leupold VX 1 on my rifle just to keep me shooting. We shot the rifle at ranges from 100yds out to almost 600yds. Throughout the magnification range the scope was always focused at all distances. I know parallax is a different issue at extended ranges.
I am searching for some rifle scopes that will meet specific criteria such as, quick target acquisition, graduated reticle, focused at multiple distances, essentially no fumbling with a focus knob but wouldn't matter if it was physically there. I am flexible with magnification but would like something in the 5-20 variable range. Thus, I would like to understand what allows a scope to remain focused at multiple distances.
Thanks,
Don
-
It’s not parallax free, basically like setting the parallax at it’s infinitely setting and leaving it there.
-
@bull81 said in Rifle scopes with no focus or parallax adjustment knob:
It’s not parallax free, basically like setting the parallax at it’s infinitely setting and leaving it there.
So if I took my TT 315M, set the parallax at infinity, adjusted the diopter to focus it would be focused at all ranges? Doesn't sound right, there must some other internal parts that have to adjust for the scope to remain focused at multiple ranges. I could definitely try that though to see for myself.
-
@bull81 said in Rifle scopes with no focus or parallax adjustment knob:
It’s not parallax free, basically like setting the parallax at it’s infinitely setting and leaving it there.
@donnie said in Rifle scopes with no focus or parallax adjustment knob:
Doesn't sound right
Because its not right.
The parallax is set internally and locked in position in non-adjustable scopes. Most are low powered, and because of the low magnification, you do not necessarily see the effects as much as if it were a high magnification scope. Also, you must remember that focus, is different from parallax. You can have a perfectly clear image, and still have parallax error. It's all in the lens stack and how they have the optical design setup.
There are also technologies that turn the job of focusing over to your eye. These scopes can work quickly, but looking through them for extended periods results in severe eye fatigue. In these optics they simply set a very long focal length. (similar to F-stop in a camera) With an F36, basically everything is in focus at all times. That doesn't mean its parallax free.
Due to the above, while the focal length may be set very long, allowing a clear picture at all ranges... the parallax error will almost always persist at any range the parallax isn't set for. A simple wiggle of your eye will reveal it. If a fixed parallax scope is set for 150yds (most common) and you are observing a target at 75yds, you will almost certainly see a significant amount of reticle movement.
Avoid the mistake of uneducated people:
Parallax is independent of focus!!!!!The diopter is to adjust the clarity/focus of the reticle ONLY. On cheap scopes, such as nightforce and other similar designs, the diopter focus can have a hugely important relationship to the parallax adjustment. With some scopes you'll actually lose the ability to remove parallax error at certain distances if your eyes require enough correction to pull the diopter adjustment out of the recommended adjustment for that particular lens system.
If you are looking for a scope with very forgiving parallax, you will find NONE better than Tangent Theta. You can set the parallax for 200yds and be able to engage targets at your leisure.
-
@orkan Thanks Greg, this is exactly what I was after.
I wrote to Armament Technologies regarding certain issues I was encountering with the 525P. Save a bunch of typing.... they provided very technical information that essentially is summmed up by the fact that nothing can be perfect over such a broad adjustment range. My eyes are able to see very fine imperfections or deviation in the focus across the lens due primarily to the shape of the glass. I revised my cheek rest to ensure i have the most repetable cheek weld and am able to stay as opticaly centered as possible. I'm sure you know exactly what is going on. This is fine for target shooting.
The purpose of the rifles I am having made is not necessarily precision or target shooting, although they are very capable. They are more for hunting or fast target acquisition and rapid shooting. With this in mind, would you still say the TT line are the best suited scopes?
Edit, I guess I am after the forgiving focus more than the parallax.
-
@donnie said in Rifle scopes with no focus or parallax adjustment knob:
They are more for hunting or fast target acquisition and rapid shooting. With this in mind, would you still say the TT line are the best suited scopes?
What animals, what terrain, and at what distances are you speaking of? I need specifics if I'm to give correct answers.
-
@orkan Typically I will be shooting white tails, wolves, coyotes. Terrain is wooded areas and coolies/valleys. Spot and stalk and lots of running shots. Typical shots are anywhere from 50-300yds, with the occasional but not likely 400-600. Off hand shooting.
-
Ever seen a 200 lb wolf? I was 185 lbs when this picture was taken in 2005. I've found a couple areas where there is always wolf sign, and I've seen and almost had some conflicts with them. Gonna hit them hard this season.
-
Here is a picture through a TT315M GenIIXR @ 6x magnification, parallax set to 100yds. Crappy cell phone pic being what it is, the image through the scope in person is ten times better than what is represented in this photo. In person, the 100yd dots are crystal clear and in focus, and so is everything else.
Bottom left of center is our rimfire challenge target at 50yds, bottom right is a plate rack at 75yds, left in front of the berm is 100yd dots. Electrical poles approx. every 100yds on the left, with the stop sign at the last pole being 1 mile away. The trees that run the horizon in the background are 2 miles away. It's an overcast hazy day today and pics through scopes are super hard to get.
The moral of the story is, if you can't make your shots with this scope, you can't make your shots with anything.
-
@donnie
Orkan explained it in more detail than me but my point was it’s not parallax free just like setting one at infinity. It’s not parallax free at infinity but it’s generally useable for the most part just not perfect.
-
@orkan Do you ever make reference marks on the parallax, white pencil crayon or paint marker? I'll email or PM you to discuss these scopes further.
-
@donnie said in Rifle scopes with no focus or parallax adjustment knob:
Do you ever make reference marks on the parallax, white pencil crayon or paint marker?
No. Focus is focus, and as you can see, you're in focus almost always on TT scopes unless you crank the magnification way up. When I'm coyote hunting, I have my 315M set on 6x. If I get ambushed, it happens quick! I've jumped on the rifle and dropped a coyote within 1-2 seconds before.
The reason you can't put markings on the knob is because parallax free is parallax free... the position of the knob is irrelevant. The only way you know, is by doing the eye wiggle and making sure. So you adjust until you're there. The parallax is so forgiving on TT's, its not an issue.
The type of shots you are describing, distances and target sizes are such that if the parallax is set to 100yds on a 315M, you can engage targets at your will without worry of issue.
-
@bull81 said in Rifle scopes with no focus or parallax adjustment knob:
Orkan explained it in more detail than me but my point was it’s not parallax free just like setting one at infinity. It’s not parallax free at infinity but it’s generally useable for the most part just not perfect.
This does not track with my experiences at all. It would almost always be better to set the focus/parallax for a close or median range, 100-200yds. Infinity setting will almost always make closer targets become severely out of focus or severely out of parallax. This is why optics with non-adjustable focus/parallax are permanently set 100-200yds, not infinity.
