I tried them both and I can't see why anybody would choose the HT. The SF has better ergonomics and a wider FOV and in my opinion is Zeiss's "Top Gun". Get the SF.
The SF and HT are different designs and there is a place for both. The SF uses lens flatteners for a flat field view and the HT does not. There are multiple posts on the forum from members who think the flat field is unnatural and prefer the view from a classic design. Some think just the opposite and prefer the flat view. Each group has a choice with the SF or the HT.
The other consideration is rolling ball. Some people pick up rolling ball in the SF 8X42 and to some extent the 10X42 along with the Swaro EL SV products, which makes them unusable. They would be candidates for the HT. Other folks have no problems with rolling ball in those models.
Nase,
I doubt Lee will give you an absolute answer to which is best but it is not because he will not make a decision. In fact he has made a decision, he bought each model! That is because they are different and serve different needs and he decided he has use for both. Lee is however the best person on the forum to explain the differences between the two.
You need to decide how you will be using the binocular and what you will be viewing. You also need to figure out what attributes are more or less important to you so you can then come up with a weighted evaluation. Attribute examples are flat field, FOV, eye relief, weight, size , color bias, focus speed and feel, etc.
If Lee or some of us have an idea of what you are after, then we can help point you to models that may be a good fit for your needs and priorities. I for one will not say one is best because each is excellent. However one may be the better choice for you.
In my case, I went with the SF because it best met my needs. I consider it more of a general purpose all around binocular and that is what I was after. The HT is known for its brightness and ability to bring out the finest detail in the most adverse conditions so if that were a high priority as might be for a wildlife biologist or a hunter on a once in a lifetime hunt, then the HT would be a great choice. I do not have that need and would much rather have the benefits of the SF wide FOV and great balance and still have superb optics.
If you are looking for one of the best overall general purpose birding binoculars without cost being an obstacle, then the Zeiss SF 8X42 should be the place to start your search.
To address your question on clearer and 3D, I never noticed a difference. If by clearer, you mean which has better resolution, then I do not know. It may not be an issue for you depending on your own acuity. Both may resolve past your own acuity level so then it would not be a factor. If you have 20/10 vision, then you might see a difference. I do not recall seeing any properly conducted documented resolution tests of these two models. They could be close enough that any difference could due to sample variation.
The 3D in the SF looks fine to me. I have looked through and compared the SF and HT and do not recall any noticeable difference in the apparent 3D. Lee may have more to offer on that. I doubt that would be a factor in deciding between the two. What would most likely impact the apparent 3d is the flat field design vs the classic design.